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Review

2D-Nanolayer (2D-NL)-Based Hybrid Materials: A Next-Generation Material for Dye-Sensitized Solar Cells

by
Mohammad Ashfaq
1,*,
Neetu Talreja
2,*,
Neha Singh
3 and
Divya Chauhan
4,*
1
Department of Biotechnology & University Centre for Research & Development (UCRD), Chandigarh University, Gharaun, Mohali 140413, Punjab, India
2
Faculty of Science and Technology, Department of Science, Alliance University, Bengaluru 562106, Karnataka, India
3
Centre for Environmental Science and Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh, India
4
Department of Drinking Water and Sanitation, Ministry of Jal Shakti, 1208-A, Pandit Deendayal Antyodaya Bhawan, CGO Complex, Lodhi Road, New Delhi 110003, Delhi, India
*
Authors to whom correspondence should be addressed.
Electronics 2023, 12(3), 570; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics12030570
Submission received: 7 December 2022 / Revised: 10 January 2023 / Accepted: 21 January 2023 / Published: 23 January 2023
(This article belongs to the Special Issue Energy Harvesting and Energy Storage Systems, Volume II)
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Abstract

:
Two-dimensional (2D) materials, an electrifying family of innovative materials, have recently attracted wide attention due to their remarkable characteristics, primarily their high optical transparency, exceptional metallic conductivity, high mechanical strength, carrier mobility, tunable band gap values, and optimum work function. Interestingly, 2D-nanosheets/nanolayers (2D-NLs) might be synthesized into single/multi-layers using simple processes such as chemical vapor deposition (CVD), chemical bath deposition (CBD), and mechanical and liquid-phase exfoliation processes that simply enhance optoelectronic properties. However, the stability of 2D-NLs is one of the most significant challenges that limits their commercialization. Researchers have been focusing on the stability of 2D-NLs with the aim of developing next-generation solar cells. Easily tunable distinctive 2D-NLs that are based on the synthesis process, surface functional groups, and modification with other materials/hybrid materials thereby improve the stability of the 2D-NLs and their applicability to the hole transport layer (HTL) and the electron transport layer (ETL) in solar cells. Moreover, metal/non-metal-based dopants significantly enhance band gap ability and subsequently improve the efficacy of dye-sensitized solar cells (DSSCs). In this context, research has focused on 2D-NL-based photoanodes and working electrodes that improve the photoconversion efficiency (PCE) and stability of DSSCs. Herein, we mainly focus on synthesizing 2D-NLs, challenges during synthesis, stability, and high-performing DSSCs.

1. Introduction

Presently, energy demand has been increasing with the growing population; globally, that inevitably decreases the amount of fossil fuels (oil, coal, and gases) and affects the environment. It is estimated that around 15 terawatts (TW) is consumed every year, which will increase to 30 TW by 2050. Approximately 80% of daily energy requirements are fulfilled by fossil fuels, whereas ~20% are fulfilled by renewable energy sources. The unremitting decrease in fossil fuels alongside increased energy consumption and environmental pollution as they burn increases the cost of raw materials/manufacturing. Usually, fossil fuel use, or the burning of fossil fuels, is a contributing factor to the production of greenhouse gases and, subsequently, global warming. Moreover, these fossil fuels are inadequate for the long term in terms of consumption rate [1,2,3,4]. Therefore, there is a need for renewable sources of energy that fulfil the energy demand without affecting the environment.
Researchers have continuously focused on fulfilling energy requirements by using renewable energy resources, especially sunlight, to produce electricity without impacting the environment. Solar power is an eco-friendly, simple, cost-effective route that converts photon energy into electricity. However, low solar conversion efficiency, non-ecofriendly materials/devices, complex fabrication processes, and the photovoltaic device’s stability remain a concern [5,6,7,8]. In this aspect, researchers have continued to devote their efforts toward the design of semiconductor materials/photovoltaic devices with higher solar conversion efficiency, a simple fabrication process, and cost-effectiveness to resolve issues related to energy industries.
Several materials have been used so far for solar cell applications, including both metals (Zn, Fe, Ni, Ce, Cu, Cd, Pb, and TiO2) and non-metals (fullerenes, carbon nanotubes (CNTs), carbon nanofibers (CNFs), graphene, graphene oxide (GO), and graphite). However, the relatively low conversion efficiency, toxicity, and stability of these metal/nonmetal-based solar cells is ongoing challenges nowadays [9,10,11,12,13,14]. Therefore, the requirement for newer materials/modifying existing semiconductor materials is to improve conversion efficiency, reduce toxicity, and enhance the stability of solar cells. In this aspect, two-dimensional nanolayers (2D-NLs) can improve solar conversion efficiency with high stability.
Recently, 2D-NLs have aroused widespread interest in their potential application in batteries, supercapacitors, environmental remediation, photocatalytic solar cells, antibiotic materials, wound dressing materials, and sensors. The 2D-NLs are in demand because of their incomparable characteristics, such as their charge carrying ability, tunable band gaps, high mechanical strength, high surface-to-volume ratios, and exceptional conductivity. Several 2D-NLs have been discovered (e.g., graphene, GO, TMDs (WS2, MoS2, TeS2, etc.), black phosphorous, blue phosphorous, C3N4, MXene, boron nitride, and borophene) and effectively applied in numerous applications, such as agriculture, photocatalysis, the development of antibiotic materials, and the production of solar cells, mainly due to their nano-size thickness [15,16,17,18,19,20,21,22,23,24,25,26,27,28]. However, maintaining efficiency with such nano-metric thicknesses is one of the major concerns when fabricating solar cells. The thickness of 2D-NLs in a photovoltaic device is related to the stability of solar cells and can be controlled by changing their synthesis processes through methods such as liquid-phase exfoliation, chemical vapor deposition (CVD), chemical bath deposition (CBD), and hydrothermal synthesis, etc. Moreover, some methods are specific to synthesized single-layered structures with a thickness of 1 to 10 nm. CVD is one of the most popular methods for controlling thickness. The synthesized 2D-NLs can be used to design high-performance photovoltaic devices/solar cells.
Numerous types of solar cells/devices can be designed using 2D-NLs (either electron-transport layers (ETLs) or hole-transport layers (HTLs)), such as dye-sensitized solar cells (DSSCs), organic–inorganic solar cells, and perovskite solar cells (PSCs), etc. However, achieving high photo conversion efficiency (PCE) and stability is still a concern, as the stability of 2D-NLs is one of the greatest challenges when designing solar cells. Therefore, research is still required to enhance the stability of 2D-NLs for solar cell application. In this aspect, several methods have been adopted to alter the electronic structure of 2D-NLs, including metal or non-metal doping and surface functionalization using organic and inorganic moieties. Tuning the electronic properties might impact the band gap structure, and lowering the conduction band up to the desired value directly impacts the efficiency of solar cells as photoelectrons might be easily captured by photoactive material and thus take part in the final reaction. Another important property that needs to be considered is the solar cell’s flexibility. Polymeric, paper, and fabric-based substrates have recently been used to achieve portability and flexibility in 2D-NLs. As these substrates can perform a dual role, (1) these substrates can provide mechanical strength to the 2D-NLs and (2) they can help enhance their surface area. This review focuses mainly on the current status of solar cells, different 2D-NL-based DSSCs, and their conversion efficiency. We also discuss the stability and performance prospects of the 2D-NL–hybrid material-based DSSCs, such as how to improve the stability of the 2D-NL hybrid materials used in high-performance DSSCs. This review might provide newer insight into the generation of next-generation solar cell devices.

2. Solar Cells and Their Current Status

The incessant growth of the market for solar cells/panels since 1980 is due to their ability to operate as multi-megawatt power plants. The current scenario of the solar cells/panels market is growth of around 30–40%; this became possible mainly due to reduced costs, better reliability, and the economic development of solar cell supply. DSSCs are feasible and appropriate replacements for conventional energy sources such as solar power. They have emerged as one of the substitutes for extensively used silicon-based photovoltaic devices that convert solar energy to electrical energy.
In contrast, modern solar cells are primarily based on the creation of electron holes composed mainly of two layers (p- and n-type semiconductor materials). Usually, in solar irradiation imposed on the p- and n-type materials, it is the electron that has been ejected that moves from one layer to another layer. It creates an electron and a hole, thus producing energy [6,8,29,30,31]. Solar cells can be categorized based on semiconductor materials, including the following: (1) Crystalline silicon (c-Si) solar cells. c-Si solar cells utilize crystalline silicon and mainly single or multi-crystalline junction types. They are normally brittle and rigid. However, they still preferred due to their cost effectiveness. (2) Thin film-based solar cells. These second-generation solar cells are fabricated using thin films to decrease the cost of manufacture, with the trade-off being lower effectiveness compared to single crystal cells (except expensive gallium arsenide (GaAs) cells). (3) Hybrid solar cells. The third-generation of solar cell technologies which mainly consists of multi-junction cells, organic photovoltaic (OPV) cells, and hybrid solar cells. Hybrid solar cells employ inorganic and organic semiconductor material combinations, which can be seen DSSCs and perovskite solar cells. Moreover, hybrid solar cells are yet to make a noteworthy entry into large-scale commercial applications [32,33,34,35,36,37,38]. Usually, materials with high power generation efficiency enable the development of smaller and more cost-effective solar cells. The highest PCE, ~25.6%, was achieved for single junction-based solar cells (monocrystalline solar cells). Moreover, monocrystalline solar cells are one of the pillars of the market. However, high production cost, a sophisticated fabrication process, and energy payback time (EPBT) remain a concern. In this aspect, researchers have focused on decreasing production costs, simplifying the fabrication process, and tuning EPBT. With the help of relatively inexpensive vapor deposition processes/equipment, researchers have successfully reduced the cost of solar cells and simplified fabrication by reducing the utilization of semiconductor materials. Vapor deposition techniques contribute considerably to the simplified fabrication of thin film-based solar cells. The highest associated PCE of ~21.5% was achieved with CdTe-solar cells, which was lower than single junction-based solar cells [39,40]. In recent years, organic and hybrid material-based solar cells have shown great potential in terms of accomplishing solar conversion efficiency and stability improvements, especially for flexible solar cell devices.

3. 2D-NL-Based Solar Active Materials

2D-NL-based materials (graphene, graphene oxide, WS2, MOS2, MXene, TiO2, and ZnO) are a newer class of materials with different characteristics, such as surface phenomena and interface chemistry with their bulk materials. Furthermore, symmetrical lowering at the interface prevents newer environments from being manageable in the bulk equivalent. Consequently, the physicochemical characteristics, such as photon involvement in redox reactions, an acid base, and catalytic reactivity, are different and maybe dissuade the design of newer materials. Therefore, 2D-NLs are considered revolutionary due to their potential to fulfil the demand for next-generation solar cells with high power conversion efficiency (PCE). In this aspect, researchers have continued to focus on developing 2D-NL-based solar cells. Usually, incorporating 2D-NLs within the solar cells might enhance charge transport and the absorption of light while suppressing the carrier recombination that leads to an enhancement in PCE with the increased fill factor (FF) and short-circuit current density (Jsc) of OSCs. Moreover, appropriate 2D-NLs might be replaced with an unstable layer of solar cells, which is one of the possible strategies for improving next-generation highly stable solar cells. With this approach, the PCE of DSSCs, organic solar cells, and organic perovskite solar cells significantly improved by more than ~12%, 18%, and 25%, respectively [41,42,43,44,45,46]. Researchers are currently focusing on newer semiconductor materials, the combination of two or three materials, or hybrid material-based solar cells that might improve PCE and stability.

4. Strategies to Improve Stability

Global energy demand and rapid population growth necessitate the high performance and stability of next-generation DSSCs. The high PCE and stability of DSSCs supports their increased share in the market. However, the stability and PCE of the DSSCs remains a concern for commercialization. Moreover, long-term uses in real-time operation remain a concern for commercialization. Numerous strategies have been applied to augment the stability and PCE of DSSCs, such as the incorporation of metals, the use of polymers or carbon, surface functionalization, the design of heterojunctions, the application of 2D-NLs, and control of the thickness of 2D-NLs. Incorporating these materials might improve dye adsorption ability and mesoporosity, help tune the band gap, and increase conductivity, thereby improving the PCE and stability of DSSCs [47,48,49,50,51].
Usually, a dopant is an impurity that is incorporated into a bulk matrix to tune/adjust semiconductor properties. With the help of dopant materials, structural and electronic properties can be easily tuned, which might be advantageous for crystallinity, band gap value, and the relocation of electrons to the conduction band. Usually, two types of dopant materials can tune the band gap value: (1) organic dopants and (2) inorganic dopants. Organic dopants such as metals can change the electronic structure of the materials and subsequently, their band gap value. Band gap tuning facilitates the movement of electrons to the next energy level so that photon energy can be easily captured. The captivated energy helps the electron eject from the valence band. Numerous studies have suggested that the metals and their oxides that efficiently decrease/increase band gap values subsequently improve the performance of the semiconductor materials [52,53,54,55,56,57]. Inorganic dopants are a class of dopants that includes carbon-based nanomaterials (CB-NMs) such as carbon nanotubes (CNTs), carbon nanofibers (CNFs), graphene, GO, and rGO. CB-NMs exhibit high tensile strength, a large surface area, and large pore size distribution and can therefore be effectively used in numerous applications, including DSSCs. Interestingly, carbon-based 2D-NLs such as graphene, GO, and rGO have gained considerable attention, particularly in terms of application in electronics and solar cells. This is largely due to their unique characteristics, such as high surface area, high conductivity, and flexibility. The conductivity of the graphene, GO, and rGO mainly depends on the number of layers that directly affect electronic properties, thus affecting the PCE of solar cells [58,59,60,61,62,63,64].
Usually, 2D-NL-based doping within the other 2D-NL materials attracts interest due to their excellent electronic, optical, and mechanical characteristics. The single/multi-layer of these dopant (2D-NLs) materials provides exceptional surface area, large pore volume, and beneficial charge transport ability, making them a favorable candidate for solar cell application as an absorbing layer, HTL, or ETL with the aim of amplifying the performance and stability of solar cells, including DSSCs. Moreover, achieving high PCE and stability with DSSCs is one of the greatest challenges for commercialization. With the incorporation of 2D-NLs, we can easily enhance the PCE and stability of the solar cells, including DSSCs. It is important to mention here that excess incorporation of dopants might decrease PCE; therefore, the optimum amount of dopants should be determined for high PCE-based DSSCs.

5. 2D-NL-Based DSSCs

DSSCs, a type of third-generation solar cell, have advanced significantly since their invention in 1991 by Brian O’Regan and Michael Grätzel. Numerous advantages make these cells exceptional solar devices, mainly recyclability, environmental friendliness, chemical stability, high energy conversion efficiency, and high artificial light performance. Moreover, roll-to-roll production and high energy efficiency are not the only advantages of using DSSCs. Since their productivity does not decline with increasing temperatures, this extends the efficiency of harvesting energy from sunlight [65,66,67,68,69,70]. DSSCs have five essential components: (1) transparent conducting oxide (TCO), i.e., glass substrate, (2) a photoanode (a coating of direct bandgap semiconductor materials on TCO), (3) a photosensitizer, (4) a cathode (carbon–platinum layer on TCO), and (5) an electrolyte [71,72,73]. When solar irradiation strikes the photoanode surface, the adsorbed dye molecules are photo-stimulated, producing excited electrons. The excited electrons move through the TCO and jump into the conduction band, producing an electric current. It is important to mention that degradation of DSSC preformation is one of the greatest challenges nowadays at multiple levels, including the molecular, module or panel, cell, and system levels. Usually, a DSSC’s complex system, either the photoanode, dye, or electrolyte on their own, does not generate electricity, but when these elements come together with an accurate balance in all aspects (mainly diffusion that effectively controls the components of solar cells) they produce solar cells with high stability [74,75,76,77]. Figure 1 shows a schematic illustration of the different components of DSSCs. In general, the PCE and stability of the DSSCs depends on each component; therefore, it is necessary to improve each component to enhance the PCE and stability of these cells. In this regard, researchers have continued looking towards newer materials with high stability and PCE for the production of next-generation solar cells.

5.1. Graphene and Its Derivative-Based DSSCs

Graphene, the first synthesized 2D-NL, has gained a remarkable amount of attention from researchers due to its unique characteristics, mainly its exceptional carrier mobility. Another class of graphene-like oxygen-containing derivatives of graphene or graphene oxide (GO) and reduced graphene oxide (rGO) has also been comprehensively applied in numerous applications (including environmental remediation, photocatalysis, energy, the dressing of materials, and solar cells) because of their high carrier mobility, great conductivity, high dispersion ability, and high biocompatibility [78,79,80]. Numerous methods and precursors have been used to synthesize graphene in order to increase the PCE of solar cells. Organic and inorganic functional groups have been incorporated within the graphene skeleton through simple covalent interaction between the GO and other functional groups, thus providing stability and PCE. Incorporating these functional moieties facilitated unceasing diffusion paths between the donor and acceptor interfaces that led to the conquest/suppression of exciton recombination and the promotion of charge transport. Graphene can be decorated with metal nanoparticles that tune intrinsic properties for photovoltaic applications. Moreover, a derivative of graphene (rGO) has good conductivity compared to GO. Furthermore, stacking interaction and poor dispersion ability make individual rGO sheets inaccessible in terms of modification or functionalization. However, research into preventing aggregation and achieving high PCE with rGO and other graphene-based composites continues. Several studies have reported about the application of graphene and graphene-based derivatives in high-performance DSSCs. For instance, Ju et al. synthesized N-doped graphene (N-graphene) using a two-step reaction sequence, which was further deposited over fluorine-doped SnO2 (FTO)/glass substrates using an electrospray technique. The synthesized N-graphene showed a PCE of 9.05% with a fill factor of 74.2% [81]. Using hydrothermal synthesis, Yu et al. synthesized dual atom (nitrogen and sulfur)-doped graphene (N-S-graphene). Nitrogen and sulfur co-doped graphene was used as a metal-free counter electrode (CE) in DSSCs. Due to the synergistic effect of dual atoms in graphene, it shows high catalytic activity towards I3− reduction. The large surface area and interconnectivity of pores facilitate mass transfer, which exhibits a PCE of 9.40% [82]. Paranthaman et al. synthesized rGO through the thermal reduction of GO and applied it as a CE in DSSCs. The surface area and pore size distribution of synthesized rGO were 110.16 m2 g−1 and 0.5182 cm3 g−1, respectively, thus supporting electrolyte migration and a higher PCE of 5.8% [83]. Casaluci et al. synthesized graphene using a liquid-phase exfoliation process and applied it as a CE for DSSCs. The data suggested that graphene-based CEs could be used effectively in DSSCs (PCE of 3.5%) [84]. Zhang et al. synthesized graphene using an exfoliation process and dispersed it onto FTO glass. The prepared graphene-based CE was annealed to create a 3D structure that improved PCE (6.81%) [85]. Prasad et al. synthesized rGO-Cu2S-based composite materials and deposited them on onto FTO glass using an electrochemical method to fabricate quantum dot-based DSSCs. Figure 2 includes SEM images of the Cu2S and rGO-Cu2S at lower and higher magnification levels. The images indicate the uniform wrapping of rGO within the Cu2S. The synthesized rGO-Cu2S nanocomposites demonstrated a PCE of 4.26% using organic electrolytes, with short-circuit current density (Jsc), open circuit voltage (Voc), and fill factor of 17.2 mA cm−2, 0.57 V, and 44%, respectively [86].
Jiang et al. synthesized Co3S4-NS-rGO-based composites using a hydrothermal process and applied them as CEs for DSSCs. The synthesized Co3S4-NS-rGO-based nanocomposite showed a PCE of 8.08%. Interestingly, Co3S4-NS shows excellent reduction skills for I3− compared to the bulk and more active sites for the catalytic reaction [87]. Ngidi et al. synthesized dual atom (pyridinic and pyrrolic N)-doped rGO (N-N-rGO) using the hydrothermal method. Synthesized dual atom-doped rGO exhibited a large surface area of 161.51 m2 g−1 and enhanced electrical conductivity of 22.07 S cm−1. The presence of dual atoms enhanced iodide reduction and subsequently led to higher PCE (4.13%) compared to pristine rGO [88]. Salleh et al. synthesized nickel sulfide-doped rGO (Ni-S-rGO) to fabricate DSSCs. The prepared Ni-S-rGO-based DSSCs showed PCE of 1.42% due to the incorporation of thiourea that improved the reduction current [89]. Khoa et al. thermally synthesized rGO and synthesized a platinum (rGO-Pt)-based nanocomposite using a spray technique to apply them as CEs in DSSCs. The data suggested that rGO-Pt improved electron transport in the photoanode, thereby leading to high PCE (5.78%). The hybrid rGO-Pt composite reduced recombination by providing electrons to the I−/I3− electrolyte, which significantly increased the PCE of DSSCs [90]. Khan et al. synthesized polypyrrole–graphene (P-graphene)-based Pt-free DSSCs. The data suggested that the P-graphene could be used effectively in DSSCs with PCE of 3.06% with 4% graphene content within the composite [91]. Oh et al. synthesized graphene-Cu2ZnNiSe4-WO3 (GCZNSW) using a hydrothermal process and applied it as a CE for DSSCs. The data indicate that the prepared GCZNSW-based hybrid composite achieved 12.16% PCE, which is greater than the Pt electrode and suggests that the prepared GCZNSW-based hybrid composite has the potential ability to replace it [92]. The aforementioned studies and Table 1 (a summary of graphene and composite DSSCs) suggests that graphene and graphene composite materials can be used efficiently as photoanode and CE materials in DSSCs due to superior performance stemming from their exceptional surface area, wide-range absorption spectrum, high conductivity, improved photon absorption, and excellent electron transport. The doping of metals/polymers within the graphene significantly affects the PCE of the DSSCs. Moreover, the environmental friendliness and high stability of graphene and its composite materials make them promising candidates for future DSSCs.

5.2. TiO2-Based DSSCs

TiO2 is the most chosen semiconductor material due to its inexpensive cost, high adsorption ability, and non-toxicity. Moreover, TiO2 is a frequently utilized semiconductor due to its excellent dispersion and degree of crystallinity. The 2D-NLs, especially those with mesoporous structure, play a crucial role in DSSCs because of their high surface area, larger pore volume, and tunable nanostructure, which results in high adsorption ability toward dye molecules and a high ability to receive electrons from an excited dye. The dye injects an electron into the conduction band of the 2D-NLs during photoexcitation, which is then followed by transmission to the reference/CE (counter) that completes the cycle. Several studies have suggested the effective use of TiO2 in DSSCs. For example, Yu et al. synthesized TiO2 nanosheets (TiO2-NS) using a hydrothermal process and HF acid was used as a shape-controlling agent for the fabrication of DSSCs. Figure 3 shows the SEM, TEM, and HR-TEM images of TiO2-NS that confirm the formation of 2D-NL-based TiO2. The high crystallinity, pore volume, and exceptional light scattering ability of TiO2-NS enable higher PCE (4.56%) compared to other types of TiO2, such as TiO2 nanoparticles (4.24%) and commercial grade T25 TiO2 nanoparticles (3.64%). The data suggest that 2D-NLs might improve the PCE of DSSCs [93]. Wu et al. synthesized TiO2-NS using a simple hydrothermal process and fabricated DSSCs where TiO2-NS was used as a scattering layer. TiO2-NS improves PCE (7.54%) compared to the use of TiO2 nanoparticles. Exceptional light scattering offers rapid charge transfer, the least resistance, and high charge collection [94]. Peng et al. synthesized TiO2-NS with a highly exposed facet (001) using a hydrothermal process and fabricated DSSCs. TiO2-NS achieved PCE of 8.77%, which was higher than commercial grade T25 TiO2 nanoparticles (6.92%) due to higher photocurrent density [95]. Laskova et al. synthesized crystal faces of (001) and (101) with TiO2-NS and tested them against DSSCs. The data indicate that the different crystal face of TiO2-NS shows different PCE, and the highest PCE (4.7%) was ultimately observed with TiO2-NS (101) [96].
Numerous modifications have been made to semiconductors with the aim of improving the photovoltaic effects of DSSCs, including the doping of transition metals and polymers. For example, Miles et al. synthesized TiO2-NS onto ZnO nanowires (TiO2-NS-ZNW) and fabricated DSSCs. Figure 4 shows the SEM and TEM images of ZnO nanowires and TiO2-NS-ZNW. The images show a uniform coating of TiO2-NS on the ZnO nanowires. The prepared TiO2-NS-ZNW-based DSSCs show 7.5% PCE, which is around 30% more than that of TiO2. The significant improvement in PCE is mainly due to the improved surface area, electron transport, and light scattering ability. Moreover, bare ZnO nanowire-based DSSCs decrease PCE and stability, whereas the smaller quantity of TiO2-NS drastically improves the performance of DSSCs [97]. Jiang et al. synthesized Niobium-doped TiO2-NS (Nb-TiO2-NS) and used it as a photoelectrode for DSSCs. The theoretical study suggested that Nb-TiO2-NS might achieve 10% PCE, which is around 22% higher than without the use of doped TiO2-based DSSCs [98]. Xu et al. synthesized g-C3N4-incorporated TiO2-NS using a simple heating process and applied it in DSSCs. The data suggested that g-C3N4-TiO2-NS is effectively used in DSSCs with a PCE of 7.34%, largely due to the additional electron in the photoanode. Moreover, incorporating urea and g-C3N4 within g-C3N4-TiO2-NS increases PCE [99]. Lin et al. synthesized ZnO-NS using the chemical bath deposition (CBD) technique and incorporated it with TiO2 (ZnO-NS/TiO2). The data indicate that the ZnO-NS-based DSSCs show PCE of 6.6%, whereas incorporating TiO2 significantly improved PCE to 7.07%, which was attributed to TiO2 increasing dye loading ability [100]. Kim et al. synthesized ZnO-NS using an electrochemical process and incorporated it with CdSe and TiO2 to produce CdSe-ZnO-NS and TiO2-ZnO-NS and applied it for the fabrication of DSSCs. The data suggested that, upon the incorporation of CdSe and TiO2 within ZnO-NS, PCE increased compared to the use of bare ZnO-NS. Moreover, CdSe-ZnO-NS-based DSSCs show the highest PCE (1.30%), whereas TiO2-ZnO-NS shows PCE of around 0.70%. The improvement in PCE is due to the inhibited recombination of electron hole pairs at the interface of CdSe and TiO2 [101]. The aforementioned studies and Table 2 suggest that TiO2-NS is the most commonly used 2D-NL in DSSCs due to its high adsorption ability, cost-effectiveness, mesoporous texture, ability to receive electrons from dye, and high crystallinity. Moreover, TiO2-NS shows higher PCE than other forms of TiO2, such as nanoparticles and commercially available TiO2, because the 2D-NL form of TiO2 increases surface area and thereby leads to higher adsorption ability toward dye molecules. Interestingly, the doping of transition metals and polymers within TiO2-NS considerably improved the PCE of DSSCs. Therefore, TiO2-NS-based hybrid materials might become next-generation materials for DSSCs with high PCE and stability.

5.3. MXene-Based DSSCs

MXenes are a newer class of transition metal carbides and/or nitrides that were discovered by Gogotsi and W. Barsoum in 2011. MXene, a newer class of ceramic material, has been attracting attention due to its high conductivity (105 S cm−1) that stems from high mechanical strength and flexibility. This high conductivity is applied in the hole transport layer, electron transport layer, and protective layer of advanced solar cells. However, synthesis complications limit their application. In particular, acid-based exfoliation requires modification in terms of synthesis, as green synthesis is preferred over the use of acids. The excessive use of strong acid (especially HF acid) for the exfoliation of MXene layers from the MAX phase requires further consideration in terms of large-scale applications. However, high tensile strength, high conductivity, and a tunable band gap prove applicability to photovoltaics.
MXene-based materials have very low band gaps, which promote recombination. The higher the recombination rate, the lower the electric properties of the NLs. To use these materials for solar cell devices, there must be a minimal band gap so that the flow of electrons from the valence band to the conduction band can be maintained. Doping and functionalization can tune the band gap of MXene-based materials [102,103,104]. MXene has gained continuous interest and is extensively used in numerous applications, including environmental remediation, photocatalysis, energy storage, solar cell, biocidal agent, and biomedical applications [20,105,106,107,108,109]. Recently, a few studies have suggested that MXene and its hybrid materials can be used effectively for the development of high-performance DSSCs. For example, Dall’Agnese et al. synthesized MXene and TiO2 (MXene-TiO2)-based photoanodes and oxidized them at a different temperature to improve the performance of DSSCs. The data suggested that upon increasing the oxidizing temperature, PCE continuously increased up to 450 °C (2.66%). However, a temperature of more than 450 °C decreased the DSSC performance, mainly due to the smaller surface area [110]. Chen et al. synthesized MXene-CoS using an etching process and a hydrothermal process. Initially, MXene was synthesized by a simple etching process that involved HF acid. Next, the heterostructure composite was synthesized using a hydrothermal process. Figure 5 shows the SEM and TEM images and elemental mapping of MXene and the MXene-CoS-based composite. The SEM images indicate that the separated MXene sheets and CoS nanoparticles attached to MXene sheets. Moreover, no changes in the layer were observed after incorporating the CoS nanoparticles into the MXene, which makes it a suitable candidate for DSSCs. The data suggest that the prepared MXene-CoS-based composite shows high electrochemical performance (8.09% PCE). The high PCE of the MXene-CoS-based composite, mainly due to MXene-NS and the incorporation of CoS nanoparticles, creates more catalytic sites that improve permeability and charge transfer; therefore, MXene might become a next-generation material that could be used in the production of solar cells [111].
Another study focused on the use of Poly (3,4-ethylene dioxythiophene) (PEDOT)-decorated MXene (PEDOT-MXene) in DSSCs. Figure 6 shows a schematic representation of the PEDOT-MXene. The PEDOT-MXene-based DSSCs showed high electrochemical activity and mass transport ability, with PCE of 7.12%. Moreover, the prepared PEDOT-MXene-based DSSCs were stable for up to 15 days and an increase in PCE of around 40% was observed, which suggests that PEDOT-MXene-based DSSCs having the potential ability to replace Pt-based DSSCs [112]. Wen et al. synthesized a MXene-reduced graphene oxide (rGO)-polyethylene oxide/poly(vinylidene fluoride-co-hexafluoropropylene) (MXene-rGO-P)-based composite for use as a printable electrolyte. The data suggested that rGO and polymer incorporation within the MXene improves PCE. The maximum PCE observed was 8.255% [113]. Ahmad et al. synthesized MXene to replace the Pt and transparent conducting oxide (TCO) layer used in DSSCs. The data suggested that TCO- and Pt-free MXene were effective when used in DSSCs, as shown by 8.68% PCE. Moreover, PCE mainly depends on the thickness of MXene. PCE increased with the increasing thickness of MXene (up to 8 µm thickness) [114]. The literature suggests that MXene can potentially be applied to the development of solar cells, especially DSSCs with high PCE, thus replacing TCO and Pt within DSSCs. Moreover, incorporating other 2D-NLs, polymers, and nanoparticles within the MXene significantly improved PCE due to enhanced surface area, conductivity, adsorption of dye/loading of dye, and permeability. Moreover, the thickness of the MXene layer is an important factor that directly affects the PCE of DSSCs.

5.4. Black Phosphorus (BP)-Based DSSCs

BP is a novel class of 2D-NL that is highly reactive under normal conditions and therefore unstable. BP was synthesized using a liquid-phase exfoliation process and demonstrated exceptional performance, mainly in terms of energy, biomedical, electronic, sensor, and solar cell applications. The high applicability of BP is mainly due to the tunable band gap value and high carrier mobility, which makes BP a promising candidate for solar cell applications. However, poor stability and high-density charge transfer limit the applicability of BP in solar cells [115,116,117,118,119]. So far, few studies have been conducted concerning the fabrication of high-performance solar cells, especially DSSCs with high stability. For instance, Xu et al. synthesized a BP-TiO2-based photoanode that was used in DSSCs. The prepared BP-TiO2-based DSSCs showed 9.73% PCE, which is higher than TiO2-based DSSCs (6.98%). Moreover, the high PCE of the BP-TiO2-based DSSCs is due to charge separation and transfer [120]. Song et al. synthesized BP-TiO2-based electrodes for the fabrication of DSSCs. The photon adsorption ability of BP-TiO2 depends on the number of layers. The BP-TiO2-based DSSCs showed high PCE that represented an improvement of ~38% compared to TiO2 [121]. For future research, surface-modified BP incorporating metals, polymers, and other 2D-NLs might provide better PCE and easily replace Pt electrodes.

5.5. Other 2D-NL-Based DSSCs

Another interesting group of 2D-NLs that has been efficiently used for solar cell applications is TMDs (MoS2, MoSe2, WS2, WSe2, TiS2, TiSe2, TeS2, VSe2, NbSe2, etc.). Usually, TMDs are mainly composed of MX2 (M (transition metal) and X (chalcogen)), where M is a sandwich between two X layers using covalent bonds and Vander Waal forces. MoS2- and WS2-NLs have been effectively used in various types of applications (including the areas of antibiotic materials, energy, the environment, and solar cells) due to their extraordinary characteristics, such as high surface area, transparency, high conductivity, a tunable band gap, and high biocompatibility [22,122,123,124,125]. The tunable band gap’s ability to change its thickness is one of the fascinating characteristics of TMDs that might be beneficial for solar cell applications [126]. Numerous TMD-based 2D-NLs have been effectively used to fabricate solar cells such as DSSCs. For instance, Gurulakshmi et al. synthesized MoS2-based CEs for DSSCs using an electrodeposition process. The data suggested that the MoS2-based CEs were effective when used in DSSCs, as shown by 4.21% PCE [127]. Vijaya et al. synthesized MoS2 and graphene-MoS2 using a hydrothermal process and fabricated CEs for DSSCs. The data suggested that graphene-MoS2 shows higher PCE (8.1%) than MoS2 (6.6%) [128]. Krishnamoorthy et al. synthesized MoS2 and a graphene-MoS2-based photoanode for DSSCs. Interestingly, the incorporation of graphene within MoS2 reduced the band gap value and reduced the recombination of electron photogeneration, thus subsequently improving PCE to 8.92%, which is higher than bare MoS2 (3.36% PCE) [129]. Menon et al. synthesized TiO2-incorporated MoS2 (TiO2-MoS2)-based photoanodes for DSSCs. The data indicate that the TiO2-MoS2-based DSSCs show a high PCE of 6.0% compared to the bare TiO2-based DSSCs (4.7% PCE), mainly due to high photoadsorption. Moreover, more than 0.1% MoS2 decreases the PCE of the DSSCs [130]. Xu et al. synthesized PEDOT-MoS2-based CEs for DSSCs. The data suggested that incorporating MoS2 within PEDOT effectively improved PCE to 7.0% [131]. Li et al. synthesized WS2-based CEs for DSSCs using the doctor blade method. Incorporation of TiO2 and carbon particles within the WS2 film improved conductivity and adhesion, thus significantly improving the PCE of the DSSCs. The fabricated DSSCs with the prepared TiO2/carbon particles/WS2-based counter showed 4.56% PCE [132]. Krishnamoorthy et al. synthesized graphene-incorporated WS2 (graphene-WS2)-based photoanodes for the fabrication of DSSCs. Incorporating graphene within WS2 improved the adsorption ability of the dye, which significantly improved PCE. The prepared graphene-WS2-based DSSCs showed 9.6% PCE. The high PCE is mainly due to the large surface area and mesoporous property of graphene-WS2-based photoanodes [133]. Huang et al. synthesized CoS2-N-C-Co-WS2-based CEs for the fabrication of DSSCs. The prepared CoS2-N-C-Co-WS2-based composite had a large surface area and yolk–shell structure that improved PCE. The prepared CoS2-N-C-Co-WS2-based DSSCs showed a high PCE of 9.21%, which is comparatively higher than Pt [134]. Hussain et al. synthesized CuS-WS2- and CuS-MoS2-based CEs to fabricate DSSCs. The sulfur-based heterostructure improved electrocatalytic activity and decreased charge transfer resistance, thus improving PCE. The prepared CuS-WS2- and CuS-MoS2-based DSSCs showed 8.21% and 7.12% PCE, which is comparable to Pt-based electrodes [135]. The aforementioned studies and Table 3 summarize the different 2D-NLs, including TMDs that are effectively used as photoanodes and CEs in the fabrication of DSSCs. Moreover, incorporating metal, carbon, and polymers significantly improved the PCE of DSSCs. Additionally, TMDs, mainly WS2 and MoS2, showed high or comparable PCE compared to the Pt-based DSSCs, suggesting that expensive Pt can be easily replaced with TMDs.

6. Conclusions

Researchers have continued to focus on the fabrication of DSSCs with different 2D-NLs (photoanode and CE) with the aim of enhancing the performance and stability of DSSCs in order to achieve higher or comparable PCE compared to commercially available solar cells. Moreover, researchers are also looking towards replacing the Pt-based electrode to reduce the cost of solar cells. Researchers and scientists in the solar cell industry are unremittingly working to develop a newer class of materials, including 2D-NL-based photoanodes and CEs that can considerably improve the PCE and stability of DSSCs. This review article focused on how 2D-NLs and their hybrid materials have been used as photoanode and CE materials in the fabrication of DSSCs. Previous studies have clearly shown that 2D-NLs significantly improve crystallinity, surface area, tuned band gap values, the adsorption of dye molecules, the migration of electrons, mass transfer, mesoporous properties, conductivity, flexibility, and electron transport while also facilitating light scattering, thereby improving the PCE of DSSCs. Moreover, incorporating dopants (metal, polymers, carbon particles, and other 2D-NLs) improved the PCE and stability of the DSSCs. It is important to mention here that the commercialization of DSSCs requires a simple process, cost-effectiveness, high PCE, and longer stability. With the help of 2D-NLs and their hybrid materials, we can easily resolve such issues and fulfil the requirements associated with the commercialization of DSSCs. Graphene-, MXene-, MoS2-, and WS2-based 2D-NLs have more active sites that facilitate the adsorption of dye molecules, thereby easily achieving high PCE and stability while also demonstrating the potential to replace Pt-based electrode materials in DSSCs. Moreover, further research on developing newer 2D-NLs and hybrid materials is still required to improve the PCE and stability of DSSCs.

Author Contributions

M.A., N.T. and D.C., conceptualized, writing, figures, and revised the manuscript. N.S. writing the manuscript. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Kannan, N.; Vakeesan, D. Solar energy for future world: A review. Renew. Sustain. Energy Rev. 2016, 62, 1092–1105. [Google Scholar] [CrossRef]
  2. Mekhilef, S.; Saidur, R.; Safari, A. A review on solar energy use in industries. Renew. Sustain. Energy Rev. 2011, 15, 1777–1790. [Google Scholar] [CrossRef]
  3. Shafiee, S.; Topal, E. When will fossil fuel reserves be diminished? Energy Policy 2009, 37, 181–189. [Google Scholar] [CrossRef]
  4. Asafu-Adjaye, J. The relationship between energy consumption, energy prices and economic growth: Time series evidence from Asian developing countries. Energy Econ. 2000, 22, 615–625. [Google Scholar] [CrossRef] [Green Version]
  5. Kumar, J.C.R.; Majid, M.A. Renewable energy for sustainable development in India: Current status, future prospects, challenges, employment, and investment opportunities. Energy Sustain. Soc. 2020, 10, 2. [Google Scholar] [CrossRef]
  6. Nayak, P.K.; Mahesh, S.; Snaith, H.J.; Cahen, D. Photovoltaic solar cell technologies: Analysing the state of the art. Nat. Rev. Mater. 2019, 4, 269–285. [Google Scholar] [CrossRef]
  7. Kirchartz, T.; Rau, U. What Makes a Good Solar Cell? Adv. Energy Mater. 2018, 8, 1703385. [Google Scholar] [CrossRef] [Green Version]
  8. Rathore, N.; Panwar, N.L.; Yettou, F.; Gama, A. A comprehensive review of different types of solar photovoltaic cells and their applications. Int. J. Ambient Energy 2021, 42, 1200–1217. [Google Scholar] [CrossRef]
  9. Zhu, H.; Wei, J.; Wang, K.; Wu, D. Applications of carbon materials in photovoltaic solar cells. Sol. Energy Mater. Sol. Cells 2009, 93, 1461–1470. [Google Scholar] [CrossRef]
  10. Deshmukh, M.A.; Park, S.-J.; Hedau, B.S.; Ha, T.-J. Recent progress in solar cells based on carbon nanomaterials. Sol. Energy 2021, 220, 953–990. [Google Scholar] [CrossRef]
  11. Fei Guo, C.; Sun, T.; Cao, F.; Liu, Q.; Ren, Z. Metallic nanostructures for light trapping in energy-harvesting devices. Light: Sci. Appl. 2014, 3, e161. [Google Scholar] [CrossRef] [Green Version]
  12. Sebastián, D.; Baglio, V.; Girolamo, M.; Moliner, R.; Lázaro, M.J.; Aricò, A.S. Carbon nanofiber-based counter electrodes for low cost dye-sensitized solar cells. J. Power Sources 2014, 250, 242–249. [Google Scholar] [CrossRef] [Green Version]
  13. Batmunkh, M.; Biggs, M.J.; Shapter, J.G. Carbon Nanotubes for Dye-Sensitized Solar Cells. Small 2015, 11, 2963–2989. [Google Scholar] [CrossRef] [PubMed]
  14. Muchuweni, E.; Martincigh, B.S.; Nyamori, V.O. Recent advances in graphene-based materials for dye-sensitized solar cell fabrication. RSC Adv. 2020, 10, 44453–44469. [Google Scholar] [CrossRef]
  15. Sun, Z.; Talreja, N.; Tao, H.; Texter, J.; Muhler, M.; Strunk, J.; Chen, J. Catalysis of Carbon Dioxide Photoreduction on Nanosheets: Fundamentals and Challenges. Angew. Chem. Int. Ed. 2018, 57, 7610–7627. [Google Scholar] [CrossRef] [PubMed]
  16. Tao, H.; Gao, Y.; Talreja, N.; Guo, F.; Texter, J.; Yan, C.; Sun, Z. Two-dimensional nanosheets for electrocatalysis in energy generation and conversion. J. Mater. Chem. A 2017, 5, 7257–7284. [Google Scholar] [CrossRef]
  17. Gasso, S.; Mahajan, A. MXene based 2D-2D heterostructures for Counter Electrode in third generation Dye Sensitized Solar Cells. Chem. Phys. Lett. 2022, 808, 140144. [Google Scholar] [CrossRef]
  18. Hussain, S.; Shaikh, S.F.; Vikraman, D.; Mane, R.S.; Joo, O.-S.; Naushad, M.; Jung, J. Sputtering and sulfurization-combined synthesis of a transparent WS2 counter electrode and its application to dye-sensitized solar cells. RSC Adv. 2015, 5, 103567–103572. [Google Scholar] [CrossRef]
  19. Talreja, N.; Chauhan, D.; Mangalaraja, R.V. Two-dimensional nanolayers for wearable supercapacitors. In Nanostructured Materials for Sustainable Energy and Environmental Remediation; IOP Publishing: Bristol, UK, 2022; pp. 3-1–3-20. [Google Scholar]
  20. Talreja, N.; Ashfaq, M.; Chauhan, D.; Mangalaraja, R.V. Cu-MXene: A potential biocide for the next-generation biomedical application. Mater. Chem. Phys. 2023, 294, 127029. [Google Scholar] [CrossRef]
  21. Chauhan, D.; Ashfaq, M.; Mangalaraja, R.V.; Talreja, N. 2D-Nanosheets Based Hybrid Nanomaterials Interaction with Plants. In Nanomaterial Interactions with Plant Cellular Mechanisms and Macromolecules and Agricultural Implications; Al-Khayri, J.M., Alnaddaf, L.M., Jain, S.M., Eds.; Springer International Publishing: Cham, Switzerland, 2023; pp. 299–316. [Google Scholar]
  22. Ashfaq, M.; Talreja, N.; Chauhan, D.; Viswanathan, M.R. Synthesis of Cu-doped 2D-WS2 nanosheet-based nano-antibiotic materials for inhibiting E. Coli and S. aureus bacterial strains. New J. Chem. 2022, 46, 5581–5587. [Google Scholar] [CrossRef]
  23. Tomy, M.; Ambika Rajappan, A.; Vm, V.; Thankappan Suryabai, X. Emergence of Novel 2D Materials for High-Performance Supercapacitor Electrode Applications: A Brief Review. Energy Fuels 2021, 35, 19881–19900. [Google Scholar] [CrossRef]
  24. Qin, Z.; Chen, Y.; Zhu, K.; Zhao, Y. Two-Dimensional Materials for Perovskite Solar Cells with Enhanced Efficiency and Stability. ACS Mater. Lett. 2021, 3, 1402–1416. [Google Scholar] [CrossRef]
  25. Lin, Q.-L.; Liang, H.; Zhou, C.-Q.; Qian, Z.-F.; Sun, Y.-L.; Wang, X.-Y.; Wang, R.-H. Defect-induced magnetism in χ3 borophene. Rare Met. 2022, 41, 3486–3494. [Google Scholar] [CrossRef]
  26. Lin, Q.-L.; Qian, Z.-F.; Dai, X.-Y.; Sun, Y.-L.; Wang, R.-H. Regulation of electronic structure of monolayer MoS2 by pressure. Rare Met. 2022, 41, 1761–1770. [Google Scholar] [CrossRef]
  27. Lin, Q.; Miao, L.; Qian, Z.; Sun, Y.; Wang, R. First-Principles Calculations on Magnetism Induced by Vacancies in β12-Borophene Nanosheets: Implications for Property Modulation. ACS Appl. Nano Mater. 2022, 5, 113–119. [Google Scholar] [CrossRef]
  28. Wang, R.; Dai, X.; Qian, Z.; Zhong, S.; Chen, S.; Fan, S.; Zhang, H.; Wu, F. Boosting Lithium Storage in Free-Standing Black Phosphorus Anode via Multifunction of Nanocellulose. ACS Appl. Mater. Interfaces 2020, 12, 31628–31636. [Google Scholar] [CrossRef]
  29. Al-Ezzi, A.S.; Ansari, M.N.M. Photovoltaic Solar Cells: A Review. Appl. Syst. Innov. 2022, 5, 67. [Google Scholar] [CrossRef]
  30. Dambhare, M.V.; Butey, B.; Moharil, S.V. Solar photovoltaic technology: A review of different types of solar cells and its future trends. J. Phys. Conf. Ser. 2021, 1913, 012053. [Google Scholar] [CrossRef]
  31. Li, J.; Aierken, A.; Liu, Y.; Zhuang, Y.; Yang, X.; Mo, J.H.; Fan, R.K.; Chen, Q.Y.; Zhang, S.Y.; Huang, Y.M.; et al. A Brief Review of High Efficiency III-V Solar Cells for Space Application. Front. Phys. 2021, 8, 631925. [Google Scholar] [CrossRef]
  32. Ushasree, P.M.; Bora, B. Chapter 1 Silicon Solar Cells. In Solar Energy Capture Materials; The Royal Society of Chemistry: London, UK, 2019; pp. 1–55. [Google Scholar]
  33. Satharasinghe, A.; Hughes-Riley, T. A Review of Solar Energy Harvesting Electronic Textiles. Sensors 2020, 20, 5938. [Google Scholar] [CrossRef]
  34. Katagiri, H.; Jimbo, K.; Maw, W.S.; Oishi, K.; Yamazaki, M.; Araki, H.; Takeuchi, A. Development of CZTS-based thin film solar cells. Thin Solid Films 2009, 517, 2455–2460. [Google Scholar] [CrossRef]
  35. Asim, N.; Mohammad, M.; Badiei, M. Chapter 8—Novel Nanomaterials for Solar Cell Devices. In Nanomaterials for Green Energy; Bhanvase, B.A., Pawade, V.B., Dhoble, S.J., Sonawane, S.H., Ashokkumar, M., Eds.; Elsevier: Amsterdam, The Netherlands, 2018; pp. 227–277. [Google Scholar]
  36. Müller-Buschbaum, P.; Thelakkat, M.; Fässler, T.F.; Stutzmann, M. Hybrid Photovoltaics—From Fundamentals towards Application. Adv. Energy Mater. 2017, 7, 1700248. [Google Scholar] [CrossRef] [Green Version]
  37. Michaels, H.; Benesperi, I.; Freitag, M. Challenges and prospects of ambient hybrid solar cell applications. Chem. Sci. 2021, 12, 5002–5015. [Google Scholar] [CrossRef] [PubMed]
  38. Lu, Z.; Hou, G.; Zhu, Y.; Chen, J.; Xu, J.; Chen, K. High efficiency organic–Si hybrid solar cells with a one-dimensional CdS interlayer. Nanoscale 2021, 13, 4206–4212. [Google Scholar] [CrossRef] [PubMed]
  39. Lin, S.; Peng, X. Current Status and Challenges of Solar Cells Based on Semiconductor Nanocrystals. Energy Fuels 2021, 35, 18928–18941. [Google Scholar] [CrossRef]
  40. Kim, M.R.; Ma, D. Quantum-Dot-Based Solar Cells: Recent Advances, Strategies, and Challenges. J. Phys. Chem. Lett. 2015, 6, 85–99. [Google Scholar] [CrossRef]
  41. Sengupta, D.; Das, P.; Mondal, B.; Mukherjee, K. Effects of doping, morphology and film-thickness of photo-anode materials for dye sensitized solar cell application—A review. Renew. Sustain. Energy Rev. 2016, 60, 356–376. [Google Scholar] [CrossRef]
  42. Devadiga, D.; Selvakumar, M.; Shetty, P.; Santosh, M.S. Recent progress in dye sensitized solar cell materials and photo-supercapacitors: A review. J. Power Sources 2021, 493, 229698. [Google Scholar] [CrossRef]
  43. Castillo-Robles, J.A.; Rocha-Rangel, E.; Ramírez-de-León, J.A.; Caballero-Rico, F.C.; Armendáriz-Mireles, E.N. Advances on Dye-Sensitized Solar Cells (DSSCs) Nanostructures and Natural Colorants: A Review. J. Compos. Sci. 2021, 5, 288. [Google Scholar] [CrossRef]
  44. Bera, S.; Sengupta, D.; Roy, S.; Mukherjee, K. Research into dye-sensitized solar cells: A review highlighting progress in India. J. Phys. Energy 2021, 3, 032013. [Google Scholar] [CrossRef]
  45. Lee, C.-P.; Li, C.-T.; Ho, K.-C. Use of organic materials in dye-sensitized solar cells. Mater. Today 2017, 20, 267–283. [Google Scholar] [CrossRef]
  46. Tontapha, S.; Uppachai, P.; Amornkitbamrung, V. Fabrication of Functional Materials for Dye-sensitized Solar Cells. Front. Energy Res. 2021, 9, 641983. [Google Scholar] [CrossRef]
  47. Zhou, Q.; Duan, J.; Duan, Y.; Tang, Q. Review on engineering two-dimensional nanomaterials for promoting efficiency and stability of perovskite solar cells. J. Energy Chem. 2022, 68, 154–175. [Google Scholar] [CrossRef]
  48. Chiu, W.-H.; Lee, K.-M.; Suryanarayanan, V.; Hsu, J.-F.; Wu, M.-C. Controlled Photoanode Properties for Large-Area Efficient and Stable Dye-Sensitized Photovoltaic Modules. Nanomaterials 2021, 11, 2125. [Google Scholar] [CrossRef]
  49. Cheng, C.-K.; Lin, C.-H.; Wu, H.-C.; Ma, C.-C.M.; Yeh, T.-K.; Chou, H.-Y.; Tsai, C.-H.; Hsieh, C.-K. The Two-Dimensional Nanocomposite of Molybdenum Disulfide and Nitrogen-Doped Graphene Oxide for Efficient Counter Electrode of Dye-Sensitized Solar Cells. Nanoscale Res. Lett. 2016, 11, 117. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  50. Hsieh, C.-T.; Yang, B.-H.; Lin, J.-Y. One- and two-dimensional carbon nanomaterials as counter electrodes for dye-sensitized solar cells. Carbon 2011, 49, 3092–3097. [Google Scholar] [CrossRef]
  51. Ghartavol, H.M.; Mohammadi, M.R.; Afshar, A.; Li, Y. On the assessment of incorporation of CNT–TiO2 core–shell structures into nanoparticle TiO2 photoanodes in dye-sensitized solar cells. Photochem. Photobiol. Sci. 2019, 18, 1840–1850. [Google Scholar] [CrossRef]
  52. Roy-Mayhew, J.D.; Aksay, I.A. Graphene Materials and Their Use in Dye-Sensitized Solar Cells. Chem. Rev. 2014, 114, 6323–6348. [Google Scholar] [CrossRef]
  53. Kim, S.-B.; Park, J.-Y.; Kim, C.-S.; Okuyama, K.; Lee, S.-E.; Jang, H.-D.; Kim, T.-O. Effects of Graphene in Dye-Sensitized Solar Cells Based on Nitrogen-Doped TiO2 Composite. J. Phys. Chem. C 2015, 119, 16552–16559. [Google Scholar] [CrossRef]
  54. Kundu, A.; Shit, A.; Nandi, S. Carbon Dot Assisted Synthesis of Nanostructured Polyaniline for Dye Sensitized Solar Cells. Energy Fuels 2017, 31, 7364–7371. [Google Scholar] [CrossRef]
  55. Talreja, N.; Ashfaq, M.; Chauhan, D.; Mera, A.C.; Rodríguez, C.A. Strategic Doping Approach of the Fe–BiOI Microstructure: An Improved Photodegradation Efficiency of Tetracycline. ACS Omega 2021, 6, 1575–1583. [Google Scholar] [CrossRef] [PubMed]
  56. Ünlü, B.; Çakar, S.; Özacar, M. The effects of metal doped TiO2 and dithizone-metal complexes on DSSCs performance. Sol. Energy 2018, 166, 441–449. [Google Scholar] [CrossRef]
  57. Kausar, A.; Sattar, A.; Xu, C.; Zhang, S.; Kang, Z.; Zhang, Y. Advent of alkali metal doping: A roadmap for the evolution of perovskite solar cells. Chem. Soc. Rev. 2021, 50, 2696–2736. [Google Scholar] [CrossRef] [PubMed]
  58. Subalakshmi, K.; Chung, W.; Lee, S. Synergistically improved photovoltaic performances of dye-sensitized solar cells with metal-free organic cosensitizer and hybrid rGO-TiO2 photoanode. Dye. Pigment. 2023, 209, 110892. [Google Scholar] [CrossRef]
  59. Wu, Q.; Chen, R.; Su, P.; Shi, D.; Zhang, Y.; Chen, K.; Li, H. Co9S8/NC@FeCoS2/NC composites with hollow yolk shell structure as the counter electrode for Pt-free dye-sensitized solar cells. Electrochim. Acta 2023, 438, 141587. [Google Scholar] [CrossRef]
  60. Van Cuong, L.; Lam Tuan Cuong, D.; Tran Trung Nghia, L.; Khac Hung, L.; Thai Hoang, N.; Tan Nhiem, L.; Trong Liem Chau, P.; Thanh Phong, M.; Huu Hieu, N. Effect of reducing agents on co-precipitation synthesis of titanium dioxide/reduced graphene oxide composite materials for upgrading the performance of dye-sensitized solar cells. Chem. Eng. Sci. 2022, 264, 118145. [Google Scholar] [CrossRef]
  61. Gupta, R.; Kumar, R.; Sharma, A.; Verma, N. Novel Cu–carbon nanofiber composites for the counter electrodes of dye-sensitized solar cells. Int. J. Energy Res. 2015, 39, 668–680. [Google Scholar] [CrossRef]
  62. Ashfaq, M.; Chauhan, D.; Mangalaraja, R.V. Micro-mesoporous carbon-based nanostructured materials for flexible supercapacitors. In Nanostructured Materials for Sustainable Energy and Environmental Remediation; IOP Publishing: Bristol, UK, 2022; pp. 4-1–4-19. [Google Scholar]
  63. Miao, X.; Tongay, S.; Petterson, M.K.; Berke, K.; Rinzler, A.G.; Appleton, B.R.; Hebard, A.F. High Efficiency Graphene Solar Cells by Chemical Doping. Nano Lett. 2012, 12, 2745–2750. [Google Scholar] [CrossRef] [Green Version]
  64. Kadam, K.D.; Rehman, M.A.; Kim, H.; Rehman, S.; Khan, M.A.; Patil, H.; Aziz, J.; Park, S.; Abdul Basit, M.; Khan, K.; et al. Enhanced and Passivated Co-doping Effect of Organic Molecule and Bromine on Graphene/HfO2/Silicon Metal–Insulator–Semiconductor (MIS) Schottky Junction Solar Cells. ACS Appl. Energy Mater. 2022, 5, 10509–10517. [Google Scholar] [CrossRef]
  65. Hagfeldt, A.; Boschloo, G.; Sun, L.; Kloo, L.; Pettersson, H. Dye-Sensitized Solar Cells. Chem. Rev. 2010, 110, 6595–6663. [Google Scholar] [CrossRef]
  66. Lin, L.-Y.; Ho, K.-C. Dye-Sensitized Solar Cells. In Encyclopedia of Modern Optics, 2nd ed.; Guenther, B.D., Steel, D.G., Eds.; Elsevier: Oxford, UK, 2018; pp. 270–281. [Google Scholar]
  67. Sharma, K.; Sharma, V.; Sharma, S.S. Dye-Sensitized Solar Cells: Fundamentals and Current Status. Nanoscale Res. Lett. 2018, 13, 381. [Google Scholar] [CrossRef]
  68. Ito, S.; Murakami, T.N.; Comte, P.; Liska, P.; Grätzel, C.; Nazeeruddin, M.K.; Grätzel, M. Fabrication of thin film dye sensitized solar cells with solar to electric power conversion efficiency over 10%. Thin Solid Films 2008, 516, 4613–4619. [Google Scholar] [CrossRef]
  69. James, E.M.; Barr, T.J.; Meyer, G.J. Evidence for an Electronic State at the Interface between the SnO2 Core and the TiO2 Shell in Mesoporous SnO2/TiO2 Thin Films. ACS Appl. Energy Mater. 2018, 1, 859–867. [Google Scholar] [CrossRef]
  70. Mathew, S.; Yella, A.; Gao, P.; Humphry-Baker, R.; Curchod, B.F.E.; Ashari-Astani, N.; Tavernelli, I.; Rothlisberger, U.; Nazeeruddin, M.K.; Grätzel, M. Dye-sensitized solar cells with 13% efficiency achieved through the molecular engineering of porphyrin sensitizers. Nat. Chem. 2014, 6, 242–247. [Google Scholar] [CrossRef] [Green Version]
  71. Deepak, T.G.; Anjusree, G.S.; Thomas, S.; Arun, T.A.; Nair, S.V.; Sreekumaran Nair, A. A review on materials for light scattering in dye-sensitized solar cells. RSC Adv. 2014, 4, 17615–17638. [Google Scholar] [CrossRef]
  72. Chen, H.; Liu, T.; Wang, B.; Liu, Z.; Li, Y.; Zhao, Q.; Wang, N.; He, H.; Liu, H.; Guo, Z. Highly efficient charge collection in dye-sensitized solar cells based on nanocomposite photoanode filled with indium-tin oxide interlayer. Adv. Compos. Hybrid Mater. 2018, 1, 356–363. [Google Scholar] [CrossRef]
  73. Snaith, H.J.; Schmidt-Mende, L. Advances in Liquid-Electrolyte and Solid-State Dye-Sensitized Solar Cells. Adv. Mater. 2007, 19, 3187–3200. [Google Scholar] [CrossRef]
  74. Iftikhar, H.; Sonai, G.G.; Hashmi, S.G.; Nogueira, A.F.; Lund, P.D. Progress on Electrolytes Development in Dye-Sensitized Solar Cells. Materials 2019, 12, 1998. [Google Scholar] [CrossRef] [Green Version]
  75. Cavallo, C.; Di Pascasio, F.; Latini, A.; Bonomo, M.; Dini, D. Nanostructured Semiconductor Materials for Dye-Sensitized Solar Cells. J. Nanomater. 2017, 2017, 5323164. [Google Scholar] [CrossRef] [Green Version]
  76. Asim, N.; Ahmadi, S.; Alghoul, M.A.; Hammadi, F.Y.; Saeedfar, K.; Sopian, K. Research and Development Aspects on Chemical Preparation Techniques of Photoanodes for Dye Sensitized Solar Cells. Int. J. Photoenergy 2014, 2014, 518156. [Google Scholar] [CrossRef] [Green Version]
  77. Kharkwal, D.; Sharma, N.; Kumar Gupta, S.; Mohan Singh Negi, C. Enhanced performance of dye-sensitized solar cells by co-sensitization of metal-complex and organic dye. Sol. Energy 2021, 230, 1133–1140. [Google Scholar] [CrossRef]
  78. Sasidharan, V.; Sachan, D.; Chauhan, D.; Talreja, N.; Ashfaq, M. Three-dimensional (3D) polymer—Metal–carbon framework for efficient removal of chemical and biological contaminants. Sci. Rep. 2021, 11, 7708. [Google Scholar] [CrossRef]
  79. Ashfaq, M.; Talreja, N.; Chauhan, D.; Rodríguez, C.A.; Mera, A.C.; Ramalinga Viswanathan, M. Synthesis of reduced graphene oxide incorporated bimetallic (Cu/Bi) nanorods based photocatalyst materials for the degradation of gallic acid and bacteria. J. Ind. Eng. Chem. 2022, 110, 447–455. [Google Scholar] [CrossRef]
  80. Ashfaq, M.; Wongpakham, T.; Talreja, N.; Chauhan, D.; Tharasanit, T.; Srituravanich, W. Synthesis of polymeric composite grafted with mineral particles/graphene oxide-based biomaterial: A promising robust hemostatic bandage. Mater. Today Commun. 2022, 33, 104786. [Google Scholar] [CrossRef]
  81. Ju, M.J.; Kim, J.C.; Choi, H.-J.; Choi, I.T.; Kim, S.G.; Lim, K.; Ko, J.; Lee, J.-J.; Jeon, I.-Y.; Baek, J.-B.; et al. N-Doped Graphene Nanoplatelets as Superior Metal-Free Counter Electrodes for Organic Dye-Sensitized Solar Cells. ACS Nano 2013, 7, 5243–5250. [Google Scholar] [CrossRef] [PubMed]
  82. Yu, Z.; Bai, Y.; Wang, Y.; Liu, Y.; Zhao, Y.; Liu, Y.; Sun, K. One-step synthesis of three-dimensional nitrogen and sulfur co-doped graphene networks as low cost metal-free counter electrodes for dye-sensitized solar cells. Chem. Eng. J. 2017, 311, 302–309. [Google Scholar] [CrossRef]
  83. Paranthaman, V.; Sundaramoorthy, K.; Chandra, B.; Muthu, S.P.; Alagarsamy, P.; Perumalsamy, R. Investigation on the Performance of Reduced Graphene Oxide as Counter Electrode in Dye Sensitized Solar Cell Applications. physica status solidi a 2018, 215, 1800298. [Google Scholar] [CrossRef]
  84. Casaluci, S.; Gemmi, M.; Pellegrini, V.; Di Carlo, A.; Bonaccorso, F. Graphene-based large area dye-sensitized solar cell modules. Nanoscale 2016, 8, 5368–5378. [Google Scholar] [CrossRef]
  85. Zhang, D.W.; Li, X.D.; Li, H.B.; Chen, S.; Sun, Z.; Yin, X.J.; Huang, S.M. Graphene-based counter electrode for dye-sensitized solar cells. Carbon 2011, 49, 5382–5388. [Google Scholar] [CrossRef]
  86. Krishna Prasad, A.; Jo, I.-R.; Kang, S.-H.; Ahn, K.-S. Novel method for synthesis of reduced graphene oxide–Cu2S and its application as a counter electrode in quantum-dot-sensitized solar cells. Appl. Surf. Sci. 2021, 564, 150393. [Google Scholar] [CrossRef]
  87. Jiang, T.; Yang, S.; Dai, P.; Yu, X.; Bai, Z.; Wu, M.; Li, G.; Tu, C. Economic synthesis of Co3S4 ultrathin nanosheet/reduced graphene oxide composites and their application as an efficient counter electrode for dye-sensitized solar cells. Electrochim. Acta 2018, 261, 143–150. [Google Scholar] [CrossRef]
  88. Ngidi, N.P.D.; Muchuweni, E.; Nyamori, V.O. Dual heteroatom-doped reduced graphene oxide and its application in dye-sensitized solar cells. Opt. Mater. 2021, 122, 111689. [Google Scholar] [CrossRef]
  89. Salleh, S.A.; Rahman, M.Y.A.; Aziz, T.H.T. Dye-sensitized solar cell using nickel sulfide-reduced graphene oxide counter electrode: Effect of sulphur content. Inorg. Chem. Commun. 2022, 135, 109086. [Google Scholar] [CrossRef]
  90. Khoa, N.T.; Thuan, D.V.; Kim, S.W.; Park, S.; Tam, T.V.; Choi, W.M.; Cho, S.; Kim, E.J.; Hahn, S.H. Facile fabrication of thermally reduced graphene oxide–platinum nanohybrids and their application in catalytic reduction and dye-sensitized solar cells. RSC Adv. 2016, 6, 1535–1541. [Google Scholar] [CrossRef]
  91. Mahmood Khan, I.; Nazar, R.; Mehmood, U. Development of polypyrrole/graphene (PPY/graphene) based electrocatalyst for platinum free dye-sensitized solar cells (DSSCs). Mater. Lett. 2022, 320, 132331. [Google Scholar] [CrossRef]
  92. Oh, W.C.; Cho, K.Y.; Jung, C.H.; Areerob, Y. Hybrid of Graphene based on quaternary Cu2ZnNiSe4 –WO3 Nanorods for Counter Electrode in Dye-sensitized Solar Cell Application. Sci. Rep. 2020, 10, 4738. [Google Scholar] [CrossRef] [Green Version]
  93. Yu, J.; Fan, J.; Lv, K. Anatase TiO2 nanosheets with exposed (001) facets: Improved photoelectric conversion efficiency in dye-sensitized solar cells. Nanoscale 2010, 2, 2144–2149. [Google Scholar] [CrossRef] [PubMed]
  94. Wu, C.; Qi, L.; Chen, Y.; Ouyang, Q.; Li, C. Dye-sensitized solar cells based on two-dimensional TiO2 nanosheets as the scattering layers. Res. Chem. Intermed. 2016, 42, 5653–5664. [Google Scholar] [CrossRef]
  95. Peng, J.-D.; Shih, P.-C.; Lin, H.-H.; Tseng, C.-M.; Vittal, R.; Suryanarayanan, V.; Ho, K.-C. TiO2 nanosheets with highly exposed (001)-facets for enhanced photovoltaic performance of dye-sensitized solar cells. Nano Energy 2014, 10, 212–221. [Google Scholar] [CrossRef]
  96. Laskova, B.; Zukalova, M.; Kavan, L.; Chou, A.; Liska, P.; Wei, Z.; Bin, L.; Kubat, P.; Ghadiri, E.; Moser, J.E.; et al. Voltage enhancement in dye-sensitized solar cell using (001)-oriented anatase TiO2 nanosheets. J. Solid State Electrochem. 2012, 16, 2993–3001. [Google Scholar] [CrossRef] [Green Version]
  97. Miles, D.O.; Lee, C.S.; Cameron, P.J.; Mattia, D.; Kim, J.H. Hierarchical growth of TiO2 nanosheets on anodic ZnO nanowires for high efficiency dye-sensitized solar cells. J. Power Sources 2016, 325, 365–374. [Google Scholar] [CrossRef] [Green Version]
  98. Jiang, L.; Sun, L.; Yang, D.; Zhang, J.; Li, Y.-J.; Deng, W.-Q. Niobium-Doped (001)-Dominated Anatase TiO2 Nanosheets as Photoelectrode for Efficient Dye-Sensitized Solar Cells. ACS Appl. Mater. Interfaces 2017, 9, 9576–9583. [Google Scholar] [CrossRef] [PubMed]
  99. Xu, J.; Wang, G.; Fan, J.; Liu, B.; Cao, S.; Yu, J. g-C3N4 modified TiO2 nanosheets with enhanced photoelectric conversion efficiency in dye-sensitized solar cells. J. Power Sources 2015, 274, 77–84. [Google Scholar] [CrossRef]
  100. Lin, C.-Y.; Lai, Y.-H.; Chen, H.-W.; Chen, J.-G.; Kung, C.-W.; Vittal, R.; Ho, K.-C. Highly efficient dye-sensitized solar cell with a ZnO nanosheet-based photoanode. Energy Environ. Sci. 2011, 4, 3448–3455. [Google Scholar] [CrossRef]
  101. Kim, Y.T.; Park, M.Y.; Choi, K.H.; Tai, W.S.; Shim, W.H.; Park, S.Y.; Kang, J.W.; Lee, K.H.; Jeong, Y.; Kim, Y.D.; et al. ZnO nanosheets decorated with CdSe and TiO2 for the architecture of dye-sensitized solar cells. J. Nanosci. Nanotechnol. 2011, 11, 2263–2268. [Google Scholar] [CrossRef] [PubMed]
  102. Saeed, M.A.; Shahzad, A.; Rasool, K.; Mateen, F.; Oh, J.-M.; Shim, J.W. 2D MXene: A Potential Candidate for Photovoltaic Cells? A Critical Review. Adv. Sci. 2022, 9, 2104743. [Google Scholar] [CrossRef] [PubMed]
  103. Yin, L.; Li, Y.; Yao, X.; Wang, Y.; Jia, L.; Liu, Q.; Li, J.; Li, Y.; He, D. MXenes for Solar Cells. Nano-Micro Lett. 2021, 13, 78. [Google Scholar] [CrossRef]
  104. Shi, Z.; Khaledialidusti, R.; Malaki, M.; Zhang, H. MXene-Based Materials for Solar Cell Applications. Nanomaterials 2021, 11, 3170. [Google Scholar] [CrossRef]
  105. Wang, Y.; Guo, T.; Tian, Z.; Bibi, K.; Zhang, Y.-Z.; Alshareef, H.N. MXenes for Energy Harvesting. Adv. Mater. 2022, 34, 2108560. [Google Scholar] [CrossRef]
  106. Sun, Y.; Li, Y. Potential environmental applications of MXenes: A critical review. Chemosphere 2021, 271, 129578. [Google Scholar] [CrossRef]
  107. Agresti, A.; Pazniak, A.; Pescetelli, S.; Di Vito, A.; Rossi, D.; Pecchia, A.; Auf der Maur, M.; Liedl, A.; Larciprete, R.; Kuznetsov, D.V.; et al. Titanium-carbide MXenes for work function and interface engineering in perovskite solar cells. Nat. Mater. 2019, 18, 1228–1234. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  108. Li, X.; Bai, Y.; Shi, X.; Su, N.; Nie, G.; Zhang, R.; Nie, H.; Ye, L. Applications of MXene (Ti3C2Tx) in photocatalysis: A review. Mater. Adv. 2021, 2, 1570–1594. [Google Scholar] [CrossRef]
  109. Ramezani Farani, M.; Nourmohammadi Khiarak, B.; Tao, R.; Wang, Z.; Ahmadi, S.; Hassanpour, M.; Rabiee, M.; Saeb, M.R.; Lima, E.C.; Rabiee, N. 2D MXene nanocomposites: Electrochemical and biomedical applications. Environ. Sci. Nano 2022, 9, 4038–4068. [Google Scholar] [CrossRef]
  110. Dall’Agnese, C.; Dall’Agnese, Y.; Anasori, B.; Sugimoto, W.; Mori, S. Oxidized Ti3C2 MXene nanosheets for dye-sensitized solar cells. New J. Chem. 2018, 42, 16446–16450. [Google Scholar] [CrossRef] [Green Version]
  111. Chen, X.; Zhuang, Y.; Shen, Q.; Cao, X.; Yang, W.; Yang, P. In situ synthesis of Ti3C2Tx MXene/CoS nanocomposite as high performance counter electrode materials for quantum dot-sensitized solar cells. Sol. Energy 2021, 226, 236–244. [Google Scholar] [CrossRef]
  112. Priya Nagalingam, S.; Grace, A.N. Poly(3,4-ethylenedioxythiophene) decorated MXene as an alternative counter electrode for dye-sensitized solar cells. Mater. Today Chem. 2022, 26, 101113. [Google Scholar] [CrossRef]
  113. Wen, J.; Sun, Z.; Qiao, Y.; Zhou, Y.; Liu, Y.; Zhang, Q.; Liu, Y.; Jiao, S. Ti3C2 MXene-Reduced Graphene Oxide Composite Polymer-Based Printable Electrolyte for Quasi-Solid-State Dye-Sensitized Solar Cells. ACS Appl. Energy Mater. 2022, 5, 3329–3338. [Google Scholar] [CrossRef]
  114. Ahmad, M.S.; Pandey, A.K.; Abd Rahim, N.; Aslfattahi, N.; Mishra, Y.K.; Rashid, B.; Saidur, R. 2-D Mxene flakes as potential replacement for both TCO and Pt layers for Dye-Sensitized Solar cell. Ceram. Int. 2021, 47, 27942–27947. [Google Scholar] [CrossRef]
  115. Yang, Y.; Gao, J.; Zhang, Z.; Xiao, S.; Xie, H.-H.; Sun, Z.-B.; Wang, J.-H.; Zhou, C.-H.; Wang, Y.-W.; Guo, X.-Y.; et al. Black Phosphorus Based Photocathodes in Wideband Bifacial Dye-Sensitized Solar Cells. Adv. Mater. 2016, 28, 8937–8944. [Google Scholar] [CrossRef]
  116. Xue, Y.; Min, S.; Wang, F. Dye-sensitized black phosphorus nanosheets decorated with Pt cocatalyst for highly efficient photocatalytic hydrogen evolution under visible light. Int. J. Hydrog. Energy 2019, 44, 21873–21881. [Google Scholar] [CrossRef]
  117. Lin, S.; Li, Y.; Qian, J.; Lau, S.P. Emerging opportunities for black phosphorus in energy applications. Mater. Today Energy 2019, 12, 1–25. [Google Scholar] [CrossRef]
  118. Chen, W.; Ouyang, J.; Liu, H.; Chen, M.; Zeng, K.; Sheng, J.; Liu, Z.; Han, Y.; Wang, L.; Li, J.; et al. Black Phosphorus Nanosheet-Based Drug Delivery System for Synergistic Photodynamic/Photothermal/Chemotherapy of Cancer. Adv. Mater. 2017, 29, 1603864. [Google Scholar] [CrossRef] [PubMed]
  119. Wang, X.; Xiang, Y.; Zhou, B.; Zhang, Y.; Wu, J.; Hu, R.; Liu, L.; Song, J.; Qu, J. Enhanced photocatalytic performance of Ag/TiO2 nanohybrid sensitized by black phosphorus nanosheets in visible and near-infrared light. J. Colloid Interface Sci. 2019, 534, 1–11. [Google Scholar] [CrossRef] [PubMed]
  120. Xu, Y.; Wang, X.; Jin, M.; Zhou, G.; Shui, L. Enhanced performance of dye-sensitized solar cells anodes modified with black phosphorus nanosheets. J. Mater. Sci. 2020, 55, 5499–5509. [Google Scholar] [CrossRef]
  121. Song, J.; Wang, J.; Lin, X.; He, J.; Liu, H.; Lei, Y.; Chu, Z. Black Phosphorus/TiO2 Composite Photoanode with Enhanced Photoelectrical Performance. ChemElectroChem 2017, 4, 2373–2377. [Google Scholar] [CrossRef]
  122. Yin, X.; Tang, C.S.; Zheng, Y.; Gao, J.; Wu, J.; Zhang, H.; Chhowalla, M.; Chen, W.; Wee, A.T.S. Recent developments in 2D transition metal dichalcogenides: Phase transition and applications of the (quasi-)metallic phases. Chem. Soc. Rev. 2021, 50, 10087–10115. [Google Scholar] [CrossRef] [PubMed]
  123. Chhowalla, M.; Liu, Z.; Zhang, H. Two-dimensional transition metal dichalcogenide (TMD) nanosheets. Chem. Soc. Rev. 2015, 44, 2584–2586. [Google Scholar] [CrossRef]
  124. Choi, W.; Choudhary, N.; Han, G.H.; Park, J.; Akinwande, D.; Lee, Y.H. Recent development of two-dimensional transition metal dichalcogenides and their applications. Mater. Today 2017, 20, 116–130. [Google Scholar] [CrossRef]
  125. Ali, M.; Afzal, A.M.; Iqbal, M.W.; Mumtaz, S.; Imran, M.; Ashraf, F.; Ur Rehman, A.; Muhammad, F. 2D-TMDs based electrode material for supercapacitor applications. Int. J. Energy Res. 2022, 46, 22336–22364. [Google Scholar] [CrossRef]
  126. Rashidi, S.; Rashidi, S.; Heydari, R.K.; Esmaeili, S.; Tran, N.; Thangi, D.; Wei, W. WS2 and MoS2 counter electrode materials for dye-sensitized solar cells. Prog. Photovolt. Res. Appl. 2021, 29, 238–261. [Google Scholar] [CrossRef]
  127. Gurulakshmi, M.; Meenakshamma, A.; Siddeswaramma, G.; Susmitha, K.; Venkata Subbaiah, Y.P.; Narayana, T.; Raghavender, M. Electrodeposited MoS2 counter electrode for flexible dye sensitized solar cell module with ionic liquid assisted photoelectrode. Sol. Energy 2020, 199, 447–452. [Google Scholar] [CrossRef]
  128. Vijaya, S.; Landi, G.; Wu, J.J.; Anandan, S. MoS2 nanosheets based counter electrodes: An alternative for Pt-free dye-sensitized solar cells. Electrochim. Acta 2019, 294, 134–141. [Google Scholar] [CrossRef]
  129. Krishnamoorthy, D.; Prakasam, A. Preparation of MoS2/graphene nanocomposite-based photoanode for dye-sensitized solar cells (DSSCs). Inorg. Chem. Commun. 2020, 118, 108016. [Google Scholar] [CrossRef]
  130. Menon, H.; Gopakumar, G.; Sankaranarayanan Nair, V.; Nair, S.V.; Shanmugam, M. 2D-Layered MoS2-Incorporated TiO2-Nanofiber- Based Dye-Sensitized Solar Cells. ChemistrySelect 2018, 3, 5801–5807. [Google Scholar] [CrossRef]
  131. Xu, T.; Kong, D.; Tang, H.; Qin, X.; Li, X.; Gurung, A.; Kou, K.; Chen, L.; Qiao, Q.; Huang, W. Transparent MoS2/PEDOT Composite Counter Electrodes for Bifacial Dye-Sensitized Solar Cells. ACS Omega 2020, 5, 8687–8696. [Google Scholar] [CrossRef] [Green Version]
  132. Li, S.; Chen, Z.; Zhang, W. Dye-sensitized solar cells based on WS2 counter electrodes. Mater. Lett. 2012, 72, 22–24. [Google Scholar] [CrossRef]
  133. Krishnamoorthy, D.; Prakasam, A. Graphene Hybridized with Tungsten disulfide (WS2) Based Heterojunctions Photoanode Materials for High Performance Dye Sensitized Solar Cell Device (DSSCs) Applications. J. Clust. Sci. 2021, 32, 621–630. [Google Scholar] [CrossRef]
  134. Huang, J.; Qian, X.; Yang, J.; Niu, Y.; Xu, C.; Hou, L. Construction of Pt-free electrocatalysts based on hierarchical CoS2/N-doped C@Co-WS2 yolk-shell nano-polyhedrons for dye-sensitized solar cells. Electrochim. Acta 2020, 340, 135949. [Google Scholar] [CrossRef]
  135. Hussain, S.; Patil, S.A.; Memon, A.A.; Vikraman, D.; Naqvi, B.A.; Jeong, S.H.; Kim, H.-S.; Kim, H.-S.; Jung, J. CuS/WS2 and CuS/MoS2 heterostructures for high performance counter electrodes in dye-sensitized solar cells. Sol. Energy 2018, 171, 122–129. [Google Scholar] [CrossRef]
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Figure 1. Schematic illustration of the different components of DSSCs.
Figure 1. Schematic illustration of the different components of DSSCs.
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Figure 2. SEM images of (a) Cu2S and (b–d) rGO-Cu2S. The images have been reproduced with permission [86].
Figure 2. SEM images of (a) Cu2S and (b–d) rGO-Cu2S. The images have been reproduced with permission [86].
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Figure 3. (a) SEM, (b,c) TEM, and (d) HR-TEM images of TiO2-NS. The images have been reproduced with permission [93].
Figure 3. (a) SEM, (b,c) TEM, and (d) HR-TEM images of TiO2-NS. The images have been reproduced with permission [93].
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Figure 4. SEM images of (a) ZnO nanowires and (b,c) TiO2-NS-ZNW and TEM images of (d) ZnO nanowires and (e,f) TiO2-NS-ZNW. The images have been reproduced with permission [97].
Figure 4. SEM images of (a) ZnO nanowires and (b,c) TiO2-NS-ZNW and TEM images of (d) ZnO nanowires and (e,f) TiO2-NS-ZNW. The images have been reproduced with permission [97].
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Figure 5. SEM images of (a) MXene and (b,c) MXene-CoS, TEM images of (d,e) MXene-CoS, and (f) an elemental mapping of MXene-CoS. The images have been reproduced with permission [111].
Figure 5. SEM images of (a) MXene and (b,c) MXene-CoS, TEM images of (d,e) MXene-CoS, and (f) an elemental mapping of MXene-CoS. The images have been reproduced with permission [111].
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Figure 6. A schematic illustration of a PEDOT-MXene-based DSSC. The images have been reproduced with permission [112].
Figure 6. A schematic illustration of a PEDOT-MXene-based DSSC. The images have been reproduced with permission [112].
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Table
Table 1. Graphene and graphene composite-based DSSCs.
Table 1. Graphene and graphene composite-based DSSCs.
S. No.Graphene and Graphene CompositesSynthesis ProcessPCE (%)RemarksReferences
1.N-grapheneE-spray deposition9.05A thin film of N-graphene-based CEs shows high PCE.[81]
2.N-S-grapheneHummer’s method9.40The dual atom (N-S) doping of graphene improved PCE. [82]
3.rGOThermal process5.8rGO facilitates electrolyte migration and, subsequently, higher PCE.[83]
4.Graphene Liquid-phase exfoliation 3.5Large surface area and high transparency might replace Pt.[84]
5.GrapheneLiquid-phase exfoliation6.81Graphene-based CE annealing creates a 3D network that improves PCE. [85]
6.rGO-Cu2SElectrochemical deposition4.26The uniform wrapping of rGO within Cu2S improved PCE. [86]
7.Co3S4-NS-rGOHydrothermal8.08Co3S4-NS improved reduction ability for I3− more than bulk and created more active sites for catalytic reaction, thereby leading to higher PCE. [87]
8.N-N-rGOHydrothermal4.13The dual atom-doped rGO improved the tri-iodic reduction reaction, thereby leading to higher PCE.[88]
9.Ni-S-rGOHummer’s method and spin coating 1.42The sulfur content improved PCE while also exhibiting a high reduction current. [89]
10.rGO-PtHummer’s method and a thermal process5.78rGO-Pt improved electron transport in the photoanode.[90]
11.P-graphenePolymerization3.06Graphene content affected PCE. [91]
12.GCZNSWHydrothermal12.16The graphene-based hybrid electrode showed higher PCE than Pt. [92]
Table
Table 2. TiO2-NS and TiO2-NS composite materials for DSSCs.
Table 2. TiO2-NS and TiO2-NS composite materials for DSSCs.
S. No.TiO2-NS and TiO2-NS CompositesSynthesis ProcessPCE (%)RemarksReferences
1.TiO2-NSHydrothermal 4.56TiO2-NS shows high PCE compared to TiO2 nanoparticles.[93]
2. TiO2-NSHydrothermal7.54TiO2-NS improves charge transfer and has the least resistance.[94]
3. TiO2-NSHydrothermal8.77TiO2-NS shows higher photocurrent density than TiO2 nanoparticles. [95]
4.TiO2-NSHydrothermal4.7Different crystal faces of TiO2-NS show different PCE. [96]
5.TiO2-NS-ZNWHydrothermal7.5The incorporation of TiO2-NS significantly improved the performance of solar cells.[97]
6.Nb-TiO2-NS--10Incorporation of Nb within Nb-TiO2-NS significantly improves PCE.[98]
7.g-C3N4-TiO2-NSHeating process7.34The incorporation of g-C3N4 within TiO2-NS significantly improves PCE.[99]
8.ZnO-NS/TiO2CBD7.07The incorporation of TiO2 within ZnO-NS significantly improved dye loading and PCE. [100]
9.CdSe-ZnO-NS and TiO2- ZnO-NSElectrochemical deposition 1.30 and 0.70The incorporation of CdSe and TiO2 within ZnO-NS significantly improved PCE.[101]
Table
Table 3. Different 2D-NLs, their hybrid material-based DSSCs, and PCE.
Table 3. Different 2D-NLs, their hybrid material-based DSSCs, and PCE.
S. No.2D-NLsSynthesis ProcessPCE (%)RemarksReferences
1.MXene-TiO2Deposition2.66Increasing the oxidizing temperature improved PCE. [110]
2.MXene-CoSEtching and hydrothermal 8.09The incorporation of CoS nanoparticles within MXene improves permeability and PCE.[111]
3.PEDOT-MXeneDeposition7.12Incorporation of PEDOT within MXene improves PCE.[112]
4.MXene-rGO-PPrinting8.255The incorporation of rGO and co-polymer improves PCE. [113]
5.MXeneEtching8.68TCO- and Pt-free DSSCs show high PCE. [114]
6.MoS2Electrodeposition4.21Surface modification of the electrode improves current density and PCE.[127]
7.MoS2 and graphene-MoS2Hydrothermal6.6 and 8.1Graphene-incorporated MoS2 shows high PCE. [128]
8.Graphene-MoS2Hydrothermal8.92Incorporation of graphene effectively reduces the band gap value and lowers photoelectron recombination. [129]
9.TiO2-MoS2Deposition6.0The incorporation of MoS2 within TiO2 increases PCE. [130]
10.PEDOT-MoS2Hydrothermal7.0Incorporation of MoS2 within PEDOT significantly improves PCE. [131]
11.TiO2/carbon particles/WS2Deposition4.56TiO2 and carbon particles incorporated within WS2 improve the film’s bonding and conductivity. [132]
12.Graphene-WS2Hydrothermal 9.6The incorporation of graphene within WS2 improves adsorption ability, thereby leading to higher PCE. [133]
13.CoS2-N-C-Co-WS2Sol–gel9.21The yolk–shell structure and high surface area improve PCE. [134]
14.CuS-WS2 and CuS-MoS2CVD8.21 and 7.12High electrocatalytic activity and low charge transfer resistance improve PCE. [135]
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Ashfaq, M.; Talreja, N.; Singh, N.; Chauhan, D. 2D-Nanolayer (2D-NL)-Based Hybrid Materials: A Next-Generation Material for Dye-Sensitized Solar Cells. Electronics 2023, 12, 570. https://0-doi-org.brum.beds.ac.uk/10.3390/electronics12030570

AMA Style

Ashfaq M, Talreja N, Singh N, Chauhan D. 2D-Nanolayer (2D-NL)-Based Hybrid Materials: A Next-Generation Material for Dye-Sensitized Solar Cells. Electronics. 2023; 12(3):570. https://0-doi-org.brum.beds.ac.uk/10.3390/electronics12030570

Chicago/Turabian Style

Ashfaq, Mohammad, Neetu Talreja, Neha Singh, and Divya Chauhan. 2023. "2D-Nanolayer (2D-NL)-Based Hybrid Materials: A Next-Generation Material for Dye-Sensitized Solar Cells" Electronics 12, no. 3: 570. https://0-doi-org.brum.beds.ac.uk/10.3390/electronics12030570

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