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Article

Synthesis and Characterization of CeO2/CuO Nanocomposites for Photocatalytic Degradation of Methylene Blue in Visible Light

1
Department of Chemistry, Government College University, Faisalabad 38000, Pakistan
2
Department of Chemistry, University of Sahiwal, Sahiwal 54000, Pakistan
3
Department of Civil and Environmental Engineering, Florida International University, Miami, FL 33301, USA
4
Chemistry Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
*
Authors to whom correspondence should be addressed.
Submission received: 24 January 2021 / Revised: 1 March 2021 / Accepted: 2 March 2021 / Published: 8 March 2021

Abstract

:
Removal of hazardous organic dyes from polluted water bodies requires the introduction of strong adsorbents and photocatalysts to industrial wastewaters. Herein, photocatalytic CeO2 nanoparticles and CeO2/CuO nanocomposite were synthesized following a co-precipitation method for low cost elution of methylene blue (MB) from water. The crystallinity and surface structure of the as-prepared materials have been analyzed using characterization techniques including X-ray powder diffraction (XRPD), field emission scanning electron microscopy (FE-SEM), energy-dispersive spectroscopy (EDS), ultra-violet visible spectroscopy (UV–Vis), and Fourier-transform infrared spectroscopy (FTIR). The average particle size of both the nano scaled samples were approximately 20–30 nm. The photocatalytic properties of CeO2/CuO were investigated under visible light against methylene blue (MB). The results showed 91% photodegradation of MB organic pollutant in 3 h as monitored by UV–Vis spectroscopy. Absorbance peaks appeared at around 670 nm corresponding to degradation of MB. Such output displayed the effectiveness of Ce nanocomposites for environmental benefits. Hence, CeO2/CuO nanocomposite could be useful for treatment of industrial wastewaters by removing hazardous MB dye.

1. Introduction

Currently, water pollution is considered one of the important factors affecting the environment [1]. Industrial effluents, especially from printing, dyeing and textile industries, have synthetic dyestuff which is lethal to aquatic life and also results in water contamination due to their frequent elusion into water bodies [2,3,4,5,6]. A considerable quantity of many dyes is released in effluents from dyeing processes and dye production units. For better living conditions, this issue must be solved [7,8]. Scientists have overcome numerous struggles to introduce and establish a substantial process for elution of hazardous dyes from the industrial effluents. However, adsorption has emerged as a preferred technique for this purpose owing to its cost effectiveness, easy operations, design simplicity, and environment friendliness [9]. Such adsorption phenomenon can be made more efficient by means of involving some photocatalytic materials that enhance the photo-degradation of hazardous dyes.
Additionally, researchers are now focusing on semiconducting material acting as photocatalysts which utilize photoelectrons to oxidize pollutants and is considered a green and cost-effective method to fix these issues [10,11,12]. These photocatalytic remediation processes have also attracted huge attention owing to their goodness in degradation of hazardous organic dyes [2,3,13]. In case of large and dense aggregates of particles, the inner particles become inactive in contrast to surface particles resulting in diminished photocatalytic activity [14] so introduction of nanosized photocatalysts results in improved photocatalytic activity, also the agglomeration of nanoparticles could be fixed by making such nanocomposites [6].
Among the lanthanides, cerium is selected due to its unique Ce+3/Ce+4 redox couple, which is capable of shifting between Ce2O3 and CeO2 in different redox conditions [6,15,16]. In lattice structure, the presence of Ce+3 is responsible for the oxygen defects in the nanoparticles by producing the oxygen vacancy to fulfill the charge deficiency [17,18]. Further Ce+4 ions have been reported to behave as electron-trapping sites to diminish the charge-pair recombination, and so enhance photocatalytic activity [19]. Ce+3 and Ce+4 have different optical properties due to different electronic structures, thus are more active for the oxidation process due to generation of more oxygen vacancies [20,21].
Moreover, the semiconductor’s photocatalytic activity could be enhanced by doping oxygen vacancies in it in a certain amount [22,23]. Doping of different semiconductors having similar band potentials could effectively construct heterojunctions which improve their charge separation efficiency. These heterojunction interfaces could behave as a transportation channel to enhance separation of electron hole pairs [24]. Only few studies have focused on physically improved CeO2 nanostructures on doping for environmental remediation [25]. Photocatalytic properties of CeO2 nanoparticles fabricated with diverse transition metal moieties like Mn, Ti, Fe, and Co were compared and it was reported that this doping affects the CeO2 nanoparticles morphology, enhances their surface area as well as absorption properties, and also leads to a decrease in rate of recombination of electron-hole pairs [26,27,28].
In addition, methylene blue is an aniline dye used in coloring of multiple manufactured items, especially wool, silk, and cotton. It is greatly detected in textile wastewater effluents. It is highly risky to human, animal, and even plant life. Therefore, removal of MB remains a prime priority of industrial societies.
In the present work, we report the impact of composite formation on the structural, photosensitive, and photocatalytic bearings of CeO2 nanostructures. The Ce–Cu nanocomposites are prepared by co-precipitation method. These as-prepared materials have been analyzed employing multiple characterization technologies and the results are described in detail. Moreover, their photocatalytic output was examined in visible light irradiation purposely for degradation of methylene blue.

2. Materials and Method

2.1. Materials

The chemical reagents utilized in the current experimental scheme were purely of analytical grade and were used without further processing. Cerium nitrate hexahydrate used as cerium precursor and cobalt nitrate hexahydrate used as cobalt precursor were purchased from Uni Chem. Chemical reagents Co., Ltd. MB was taken from Sigma Aldrich (Berlin, Germany). Double distilled water was preferably used for preparation of aqueous solutions.

2.2. Synthesis of CeO2 Nanoparticles

CeO2-NPs (nanoparticles) were synthesized following the co-precipitation technique. Acting as precursor, 10.85 g of Ce (NO3)3·6H2O was dissolved in double distilled water (250 mL). This mixture was heated along with stirring and the pH of solution was changed to 11 by continuous pouring of 0.1 M NaOH drop-wise. Dispersion was thus obtained. This growth solution was heated with stirring at 70 °C for 6–7 h. Subsequently, the precipitates were collected, filtered, and washed with water and ethanol, dried in oven at 85 °C, and then calcined at 600 °C for 7 h.

2.3. Preparation of CeO2-CuO Nanocomposite

Cerium copper nanocomposite was synthesized using the same method. A 0.1 M solution of Ce (NO3)3·6H2O and 5% of 0.1 M copper nitrate hexahydrate solution were mixed, and the pH of the solution raised to 11 by adding 0.1 M NaOH drop-wise with continuous stirring and heating at 70 °C. After 6–7 h of stirring, filtrating and washing of precipitates with double distilled water and ethanol was performed. The oven-dried residue at 85 °C was grinded and calcined at 600 °C for 7 h. Moreover, the physical picture of synthesis of nanocomposite can be understood by Figure 1.

2.4. Photocatalytic Activity

Aqueous solution of MB was used to estimate the catalytic activity of the photocatalysts. Extent of photodegradation by the photocatalysts under sunlight irradiation was estimated using the UV/Vis spectrophotometer. Reaction solutions were made by adding the required amount of the as-prepared nanocomposites into 500 mL of 0.03 mM MB solution exhibiting initial pH 5. This suspended mixture was then followed by stirring in the dark for approximately 30 min until an equilibrium was achieved.
The suspension was stirred in the dark for 30 min for adsorption–desorption equilibrium. The MB-containing aqueous solution and the added photocatalyst were placed in direct sunlight with constant stirring. The analytical samples from the suspension were collected at regular intervals of time, i.e. 30 min, centrifuged and filtered to remove the photocatalyst. Moreover, UV–visible spectrophotometer was used to analyze the MB concentration in analytical samples. Figure 2 represents a proposed mechanism of MB degradation using synthesized catalysts.
A conceivable mechanism involves the electron quenching/injection from photo-excited molecules of methylene blue to CeO2/CuO. Molecular oxygen in the solution mixture was then reduced followed by oxidative decomposition of MB, termed as photosensitization. The degradation mechanism fundamentally depends upon electron-hole separation, i.e., e–h charge. Herein, visible light radiation energy corresponds to band gap energy of catalytic material which excites the electrons to conduction band from valence bond. In this way, the hole created in the valence band provides a platform to degradation (oxidation/reduction) of methylene blue aided by the creation of free radicals. Excited electrons strike the nearest oxygen and form superoxide anion radical (O2), which further reacts with hydroxyl radicals and protons from water to form H2O2. In this system, this electron-hole separation is generated by visible light by water splitting into radicals and these radicals are means of dye degradation.
Percentage degradation was estimated with help of Equation (1) [29].
Percentage of degradation = C0 −Ct / C0 × 100
Here, C0 corresponds to initial absorbance of the MB solution and Ct represents the absorbance of the solution at the aforementioned time.

2.5. Characterization of Nanocomposites

The crystalline nature of the as-prepared photocatalysts was observed by using diffractometer with a scan rate 0.4° per minute in the 2θ range from 10° to 70°. The average crystallite size is calculated by applying the Scherrer equation [30].
D = 0. 89 λ/β·cosθ
D represents the average crystallite size of the samples, λ stands for X-ray wavelength, β refers to the full-width-half-maximum (FWHM) in radians, while θ denotes the Bragg’s angle.
Fourier-transform infrared (FT-IR) spectral analysis is done on a FT-IR spectrophotometer (Perkin Elmer, Überlingen England) with the range between 500 and 4000 cm−1 for functional group determination. Surface morphology of the prepared samples was determined using (cube compact model, Emcraft Seoul, South Korea) scanning electron microscope (SEM). With this instrument, the elemental analysis and sample purity were also analyzed by energy dispersive spectroscopy (EDS). The UV–vis absorbance spectra were acquired for the nanocomposites using a UV–Vis spectrophotometer (Tensor II BRUKER, Massachusetts, USA). The spectra were recorded at room temperature in air at the wavelength in range of 200 to 800 nm. The dye concentration was analyzed by UV/Vis professional double beam spectrophotometer (C-7200S, Peak Instruments, Buxton, UK).

3. Results and Discussion

The phase structure of the as-proposed catalytic materials and their respective average crystallite size were determined using X-ray powder diffraction (XRPD) analysis. Figure 3 shows XRD spectra of both nanocomposites CeO2/ CuO. The diffraction peaks were observed at 2θ = 33.2 (200), 28.2 (111), and 56.2 (311) showing the face centered cubic phase of CeO2 in the synthesized catalysts. This pattern matches with JCPDS file no. 65-2975 [4]. The XRD peaks correlates closely with XRD patterns of a reported ceria [31]. The peak at 47.6 (220) corresponds to characteristic of CuO as reported earlier [32,33]. The sharp peaks observed in the XRD patterns indicated that the prepared nanocomposites were highly crystallized. The calculated average crystalline sizes of the cerium and cerium copper nanocomposites comes to be 20.73 and 23.22 nm respectively.
The FTIR patterns of catalysts is displayed in Figure 3b. In spectrum, three main FTIR regions are observed, first between 3500 and 3000 cm−1, second in the range of 1300 and 1800 cm−1, and third in the range of 500 cm−1 [28]. The peaks at 3700 cm−1 are related to the O–H stretching mode of OH of the adsorbed water on the surface of the catalyst. The wider absorption peak appearing at 3446 cm−1 is associated to O–H stretching vibrations of the OH group. The band at 1541 cm−1 is due to H–O–H bending vibration mode of water. The third low wave number region absorption below 500 cm−1 could be assigned to Ce–O and Cu–O stretching vibrational mode as oxides form bonds in this region [34].
Figure 4 reveals the surface morphologies of the cerium nanocomposites. SEM micrographs of the Ce–Cu nanocomposite is shown in Figure 4a. In the micrograph, large aggregates consisting of fine particles of CeO2 are seen. The average particle size cis approximately 25–30 nm [2,8]. Although, the images revealed some agglomerations, it is obvious that these nanocomposites form a heterogeneous surface structure that assist in catalysis.
Energy dispersive spectroscopy (EDS) was performed in addition to SEM at the same instrument and it was assessed that the as-proposed photocatalytic materials are quite pure, and almost appropriate and predictable percentage abundance appeared. The EDS spectrum is displayed in Figure 4d which confirms the sample purity of as-synthesized composites. However, Figure 4e presents the % abundance of elements in composite material and it validates the presence of the anticipated amount of every element put in the catalysts’ synthesis.
The UV–vis spectrophotometer was used to estimate the absorption wavelength of the prepared nanocomposites. This is indispensable to estimate the energy of incident light radiation, which is either corresponding to or larger than the photocatalytic band-gap energy, so that sufficient electrons can be excited the conduction band of the photocatalysts [35]. Consequently, the absorption wavelength of the created CeO2/CuO composites is measured using a spectrophotometer. The output expressed in Figure 5a presents that the pure semiconductor oxides have a very sharp band edge [36], whereas the nanocomposite showed absorbance over a wider range, which led to a red shift in of the spectrum. This wider band edge for amorphous Ce2O3 has been speculated to arise from the formation of Ce3+ ions that have induced some localized mid-gap states in the band gap [37,38]. Furthermore, an increase in delocalization in organic dye molecules leads to small energy gap between ground and excited states, therefore a red shift was observed. The red shifts experienced in absorbance reflect an increase in π-electrons delocalization in the MB molecule [39]. As the UV–vis response proves, the nanocomposite can absorb the visible light and produce a large number of photo-generated charge pairs under sunlight irradiation. These results are also in accordance with the photocatalytic reactions results, that the holes and electrons participate commendably in oxidation and reduction reactions to degrade organic compounds [40].

4. Measurement of Photocatalytic Activity

There are many dye degradation studies using metal oxides as photocatalysts [35,41,42,43,44]. These research articles revealed the usefulness of CeO2 in photocatalytic reactions. Chaudhary et al., 2020 [45] studied synthesis of ceria nanoparticles which give photocatalytical activity against methylene blue and dye degraded in 9 h. Rao et al., 2015 [46] synthesized CuO nanoparticles and used them for photocatalytical activity of methylene blue and in 6 h. This study focuses on synthesis of the CeO/CuO nanocomposite which enhances photocatalytical activity and degrade it into 150 min (Table 1).
The combination of metal oxides incorporated in a composite may result in enrichment of surface oxygen defects. The increased concentration of surface oxygen defects can hold more photo generated electrons and holes individually and confirm their availability in decomposition organic pollutants. It accelerated the degradation of dyes and thus enhanced photo catalysis rate [35,45]. The photocatalytic response of the CeO2/CuO composite were evaluated using degradation of methylene blue under direct sunlight exposure. Figure 2 shows the discoloration of MB by CeO2/CuO catalyst under visible light irradiation which indicates the degradation of MB accompanied with CeO2/CuO composites.
In this experiment, 0.03 mM solution of MB was degraded using 1 g/L of CeO2/CuO nanocomposites. It is seen that without catalyst there was no degradation of the dye solution observed in bright sunlight which exposed no decolorization. This shows that light itself plays no part in the discoloration of MB. Initially, the reaction mixture was retained in the dark for 30 min to discern the extent of adsorption. After that, the mixture was shifted to visible light followed by constant stirring. With the procession of reaction, 4 mL of the aliquot solutions were separated through a pipette after 30 min sequel, and measured the absorption in UV–Vis spectrophotometers. Moreover, the reaction mixture was kept in the dark for 30 min, which experienced a little drop in the dye concentration. Hence, it is obvious that the catalyst is not so efficient in dark. It is obvious from Figure 6a that complete degradation of MB was achieved after 2.5 h, so CeO2/CuO are observed to degrade the dye effectively. Moreover, Figure 6b shows that photocatalyzed degradation of MB is administered by first order kinetics equation because the plot between –ln (A/Ao) vs. time demonstrated linearity in the presence of as-proposed CeO2/CuO nanocatalysts [46].
A few of the most efficient photocatalysts for dye degradation are compared with as-proposed photocatalysts in Table 2. It can be observed that the catalysts with maximum efficiency took prolonged time, however more fast catalysts revealed lower efficiency. Hence, the as-synthesized photocatalyst could be more efficient as well as faster degradation catalysts towards MB degradation.

5. Conclusions

Well crystallized CeO2/CuO nanoparticles were successfully prepared at low temperature via simple co-precipitation routes. Multiple characterization technologies were adapted to investigate the physio chemical and optical nature of the as-synthesized photocatalysts. The XRD results show that well-crystallized nanocomposites have been obtained and the average crystallite size estimated was 20–25 nm. With respect to catalytic significance, the as-synthesized CeO2/CuO nanoparticles demonstrated many selective and commendable photocatalytic possessions toward MB degradation. CeO2/CuO nanomaterials degraded the methylene blue up to approximately to 85.66% in 150 min, hence proving the strong catalytic performance of catalysts. Therefore, CeO2/CuO nanocomposites could act as a promising candidate for MB degradation in a multitude of industrial wastewater treatment plants.

Author Contributions

Conceptualization, A.R and M.A.J.; methodology, M.A.J.; software, T.S.A.; validation, A.R., M.A.J. and I.A.; formal analysis, I.A.; investigation, I.A.; resources, M.S.; data curation, T.S.A.; writing—original draft preparation, A.R.; writing—review and editing, M.A.J.; visualization, M.A.J.; supervision, M.A.J.; project administration, I.A.; funding acquisition, T.S.A. All authors have read and agreed to the published version of the manuscript.

Funding

This work was funded by the Department of Chemistry, Government College University Faisalabad, Pakistan, and Researchers Supporting Project Number (RSP-2020/254) King Saud University, Riyadh, Saudi Arabia.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

No new data were created or analyzed in this study. Data sharing is not applicable to this article.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Zhang, Q.; Zhao, X.; Duan, L.; Shen, H.; Liu, R. Controlling oxygen vacancies and enhanced visible light photocatalysis of CeO2/ZnO nanocomposites. J. Photochem. Photobiol. A Chem. 2020, 392, 112156. [Google Scholar] [CrossRef]
  2. Rajendran, S.; Khan, M.M.; Gracia, F.; Qin, J.; Gupta, V.K.; Arumainathan, S. Ce3+-ion-induced visible-light photocatalytic degradation and electrochemical activity of ZnO/CeO2 nanocomposite. Sci. Rep. 2016, 6, 31641. [Google Scholar] [CrossRef] [Green Version]
  3. Ameen, S.; Akhtar, M.S.; Seo, H.-K.; Shin, H.-S. Solution-processed CeO2/TiO2 nanocomposite as potent visible light photocatalyst for the degradation of bromophenol dye. Chem. Eng. J. 2014, 247, 193–198. [Google Scholar] [CrossRef]
  4. Saravanan, R.; Karthikeyan, N.; Govindan, S.; Narayanan, V.; Stephen, A. Photocatalytic degradation of organic dyes using ZnO/CeO2 nanocomposite material under visible light. Adv. Mater. Res. 2012, 584, 381–385. [Google Scholar] [CrossRef]
  5. Aravind, M.; Aravind, M.; Ahmad, A.; Ahmad, I.; Amalanathan, M.; Naseem, K.; Mary, S.M.M.; Parvathiraja, C.; Hussain, S.; Algarni, T.S.; et al. Critical green routing synthesis of silver NPs using jasmine flower extract for biological activities and photocatalytical degradation of methylene blue. J. Environ. Chem. Eng. 2021, 9, 104877. [Google Scholar]
  6. Ahmad, A.; Ahmad, A.; Jini, D.; Aravind, M.; Parvathiraja, C.; Ali, R.; Kiyani, M.Z.; Alothman, A. A novel study on synthesis of egg shell based activated carbon for degradation of methylene blue via photocatalysis. Arabian J. Chem. 2020, 13, 8717–8722. [Google Scholar] [CrossRef]
  7. Khataee, A.; Gholami, P.; Kalderis, D.; Pachatouridou, E.; Konsolakis, M. Preparation of novel CeO2-biochar nanocomposite for sonocatalytic degradation of a textile dye. Ultrason. Sonochem. 2018, 41, 503–513. [Google Scholar] [CrossRef]
  8. Arshad, T.; Khan, S.A.; Faisal, M.; Shah, Z.; Akhtar, K.; Asiri, A.M.; Ismail, A.A.; Alhogbi, B.G.; Khan, S.B. Cerium based photocatalysts for the degradation of acridine orange in visible light. J. Mol. Liq. 2017, 241, 20–26. [Google Scholar] [CrossRef]
  9. Rafatullah, M.; Sulaiman, O.; Hashim, R.; Ahmad, A. Adsorption of methylene blue on low-cost adsorbents: A review. J. Hazard. Mater. 2010, 177, 70–80. [Google Scholar] [CrossRef]
  10. Hussain, S.; Khan, A.J.; Arshad, M.; Javed, M.S.; Ahmad, A.; Shah, S.S.A.; Khan, M.R.; Akram, S.; Ali, S.; ALOthman, Z.A.; et al. Charge storage in binder-free 2D-hexagonal CoMoO4 nanosheets as a redox active material for pseudocapacitors. Ceram. Int. 2021, 47. [Google Scholar] [CrossRef]
  11. Naseem, K.; Zia Ur Rehman, M.; Ahmad, A.; Dubal, D.; AlGarni, T.S. Plant Extract Induced Biogenic Preparation of Silver Nanoparticles and Their Potential as Catalyst for Degradation of Toxic Dyes. Coatings 2020, 10, 1235. [Google Scholar] [CrossRef]
  12. Pirhashemi, M.; Habibi-Yangjeh, A.; Pouran, S.R. Review on the criteria anticipated for the fabrication of highly efficient ZnO-based visible-light-driven photocatalysts. J. Ind. Eng. Chem. 2018, 62, 1–25. [Google Scholar] [CrossRef]
  13. Gröttrup, J.; Schütt, F.; Smazna, D.; Lupan, O.; Adelung, R.; Mishra, Y.G. Porous ceramics based on hybrid inorganic tetrapodal networks for efficient photocatalysis and water purification. Ceram. Int. 2017, 43, 14915–14922. [Google Scholar] [CrossRef]
  14. Zhang, X.Z.; Xu, P.H.; Liu, G.W.; Ahmad, A.; Chen, X.H.; Zhu, Y.L.; Qiao, G.J. Synthesis, characterization and wettability of Cu-Sn alloy on the Si-implanted 6H-SiC. Coatings 2020, 10, 906. [Google Scholar] [CrossRef]
  15. Kashif, M.; Jaafar, E.; Bhadja, P.; Low, F.W.; Sahari, S.K.; Hussain, S.; Loong, F.K.; Ahmad, A.; AlGarni, T.S.; Shafa, M.; et al. Effect of Potassium Permanganate on Morphological, Structural and Electro-Optical Properties of Graphene Oxide Thin Films. Arabian J. Chem. 2021, 14, 102953. [Google Scholar] [CrossRef]
  16. Saleem, M.; Irfan, M.; Tabassum, S.; Albaqami, M.D.; Javed, M.S.; Hussain, S.; Pervaiz, M.; Ahmad, I.; Ahmad, A.; Zuber, M. Experimental and Theoretical Study of Highly Porous Lignocellulose Assisted Metal Oxide Photoelectrodes for Dye-sensitized Solar Cells. Arabian J. Chem. 2021, 14, 102937. [Google Scholar]
  17. Miri, A.; Sarani, M. Biosynthesis, characterization and cytotoxic activity of CeO2 nanoparticles. Ceram. Int. 2018, 44, 12642–12647. [Google Scholar] [CrossRef]
  18. Choudhury, B.; Chetri, P.; Choudhury, A. Oxygen defects and formation of Ce3+ affecting the photocatalytic performance of CeO2 nanoparticles. RSC Adv. 2014, 4, 4663–4671. [Google Scholar] [CrossRef]
  19. Li, Z.; Zhang, J.; Lv, J.; Lu, L.; Liang, C.; Dai, K. Sustainable synthesis of CeO2/CdS-diethylenetriamine composites for enhanced photocatalytic hydrogen evolution under visible light. J. Alloy. Compd. 2018, 758, 162–170. [Google Scholar] [CrossRef]
  20. Li, Z.; Yu, T.; Zou, Z. Degradation in photocatalytic activity induced by hydrogen-related defects in nano-LiNbO3 material. Appl. Phys. Lett. 2006, 88, 071917. [Google Scholar] [CrossRef]
  21. Li, T.B.; Chen, G.; Zhou, C.; Shen, Z.Y.; Jin, R.C.; Sun, J.X. New photocatalyst BiOCl/BiOI composites with highly enhanced visible light photocatalytic performances. Dalton Trans. 2011, 40, 6751–6758. [Google Scholar] [CrossRef]
  22. Wang, J.; Xia, Y.; Dong, Y.; Chen, R.; Xiang, L.; Komarneni, S. Defect-rich ZnO nanosheets of high surface area as an efficient visible-light photocatalyst. Appl. Catal. B Environ. 2016, 192, 8–16. [Google Scholar] [CrossRef] [Green Version]
  23. Li, X.; Song, J.; Liu, Y.; Zeng, H. Controlling oxygen vacancies and properties of ZnO. Curr. Appl. Phys. 2014, 14, 521–527. [Google Scholar] [CrossRef]
  24. Habibi-Yangjeh, A.; Shekofteh-Gohari, M. Novel magnetic Fe3O4/ZnO/NiWO4 nanocomposites: Enhanced visible-light photocatalytic performance through pn heterojunctions. Sep. Purif. Technol. 2017, 184, 334–346. [Google Scholar] [CrossRef]
  25. Saranya, J.; Ranjith, K.S.; Saravanan, P.; Mangalaraj, D.; Kumar, R.T.R. Cobalt-doped cerium oxide nanoparticles: Enhanced photocatalytic activity under UV and visible light irradiation. Mater. Sci. Semicond. Process. 2014, 26, 218–224. [Google Scholar] [CrossRef]
  26. Yue, L.; Zhang, X.-M. Structural characterization and photocatalytic behaviors of doped CeO2 nanoparticles. J. Alloy. Compd. 2009, 475, 702–705. [Google Scholar] [CrossRef]
  27. Arul, N.S.; Mangalaraj, D.; Chen, P.C.; Ponpandian, N.; Meena, P.; Masuda, Y. Enhanced photocatalytic activity of cobalt-doped CeO2 nanorods. J. Sol-Gel Sci. Technol. 2012, 64, 515–523. [Google Scholar] [CrossRef]
  28. Nasir, M.; Bagwasi, S.; Jiao, Y.; Chen, F.; Tian, B.; Zhang, J. Characterization and activity of the Ce and N co-doped TiO2 prepared through hydrothermal method. Chem. Eng. J. 2014, 236, 388–397. [Google Scholar] [CrossRef]
  29. Abdollahi, Y.; Abdullah, A.H.; Zainal, Z.; Yusof, N.A. Photocatalytic degradation of p-Cresol by zinc oxide under UV irradiation. Int. J. Mol. Sci. 2012, 13, 302–315. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  30. Holzwarth, U.; Gibson, N. The Scherrer equation versus the ‘Debye-Scherrer equation’. Nat. Nanotechnol. 2011, 6, 534. [Google Scholar] [CrossRef]
  31. Zhou, G.; Shah, P.R.; Montini, T.; Fornasiero, P.; Gorte, R.J. Oxidation enthalpies for reduction of ceria surfaces. Surf. Sci. 2007, 601, 2512–2519. [Google Scholar] [CrossRef] [Green Version]
  32. Lanje, A.S.; Sharma, S.J.; Pode, R.B.; Ningthoujam, R.S. Synthesis and optical characterization of copper oxide nanoparticles. Adv. Appl. Sci. Res. 2010, 1, 36–40. [Google Scholar]
  33. Wongpisutpaisan, N.; Charoonsuk, P.; Vittayakorn, N.; Pecharapa, W. Sonochemical synthesis and characterization of copper oxide nanoparticles. Energy Procedia 2011, 9, 404–409. [Google Scholar] [CrossRef] [Green Version]
  34. Magdalane, C.M.; Kaviyarasu, K.; Judith Vijaya, J.; Jayakumar, C.; Maaza, M.; Jeyaraj, B. Photocatalytic degradation effect of malachite green and catalytic hydrogenation by UV–illuminated CeO2/CdO multilayered nanoplatelet arrays: Investigation of antifungal and antimicrobial activities. J. Photochem. Photobiol. B Biol. 2017, 169, 110–123. [Google Scholar] [CrossRef]
  35. Saravanan, R.; Gupta, V.K.; Narayanan, V.; Stephen, A. Comparative study on photocatalytic activity of ZnO prepared by different methods. J. Mol. Liq. 2013, 181, 133–141. [Google Scholar] [CrossRef]
  36. Kang, Y.; Yang, Y.; Yin, L.-C.; Liu, G.; Cheng, H.-M. An amorphous carbon nitride photocatalyst with greatly extended visible-light-responsive range for photocatalytic hydrogen generation. Adv. Mater. 2015, 27, 4572–4577. [Google Scholar] [CrossRef] [PubMed]
  37. Khan, M.M.; Ansari, S.A.; Pradhan, D.; Han, D.H.; Lee, J.; Cho, M.H. Defect-induced band gap narrowed CeO2 nanostructures for visible light activities. Ind. Eng. Chem. Res. 2014, 53, 9754–9763. [Google Scholar] [CrossRef]
  38. Ansari, S.; Khan, M.M.; Ansari, M.O.; Kalathil, S.; Lee, J.; Cho, M.H. Band gap engineering of CeO2 Nanostructure by electrochemically active biofilm for visible light applications. RSC Adv. 2014, 4, 16782–16791, Erratum New J. Chem. 2016, 40, 3000–3009. [Google Scholar] [CrossRef]
  39. Nathans, J. Determinants of visual pigment absorbance: Identification of the retinylidene Schiff’s base counterion in bovine rhodopsin. Biochemistry 1990, 29, 9746–9752. [Google Scholar] [CrossRef] [PubMed]
  40. Saravanan, R.; Gupta, V.K.; Narayanan, V.; Stephen, A. Visible light degradation of textile effluent using novel catalyst ZnO/γ-Mn2O3. J. Taiwan Inst. Chem. Eng. 2014, 45, 1910–1917. [Google Scholar] [CrossRef]
  41. Chae, B.W.; Amna, T.; Shamshi Hassan, M.; Al-Deyab, S.S.; Khil, M.-S. CeO2-Cu2O composite nanofibers: Synthesis, characterization photocatalytic and electrochemical application. Adv. Powder Technol. 2017, 28, 230–235. [Google Scholar] [CrossRef]
  42. Chen, Q.; He, Q.; Lv, M.; Liu, X.; Wang, J.; Lv, J. The vital role of PANI for the enhanced photocatalytic activity of magnetically recyclable N–K2Ti4O9/MnFe2O4/PANI composites. Appl. Surf. Sci. 2014, 311, 230–238. [Google Scholar] [CrossRef]
  43. Wen, X.-J.; Niu, C.-G.; Ruan, M.; Zhang, L.; Zeng, G.-M. AgI nanoparticles-decorated CeO2 microsheets photocatalyst for the degradation of organic dye and tetracycline under visible-light irradiation. J. Colloid Interface Sci. 2017, 497, 368–377. [Google Scholar] [CrossRef] [PubMed]
  44. Yusoff, N.; Huang, N.M.; Muhamad, M.R.; Kumar, S.V.; Lim, H.N.; Harrison, I. Hydrothermal synthesis of CuO/functionalized graphene nanocomposites for dye degradation. Mater. Lett. 2013, 93, 393–396. [Google Scholar] [CrossRef]
  45. Subhan, M.A.; Ahmed, T.; Uddin, N.; Azad, A.K.; Begum, K. Synthesis, characterization, PL properties, photocatalytic and antibacterial activities of nano multi-metal oxide NiO⋅ CeO2⋅ ZnO. Spectrochim. Acta Part A Mol. Biomol. Spectrosc. 2015, 136, 824–831. [Google Scholar] [CrossRef]
  46. Ahmad, I.; Khan, S.B.; Kamal, T.; Asiri, A.M. Visible light activated degradation of organic pollutants using zinc–iron selenide. J. Mol. Liq. 2017, 229, 429–435. [Google Scholar] [CrossRef]
  47. Magdalane, C.M.; Kaviyarasu, K.; Priyadharsini, G.M.A.; Bashir, A.K.H.; Mayedwa, N.; Matinise, N.; Isaev, A.B.; Al-Dhabi, N.A.; Arasu, M.V.; Arokiyaraj, S.; et al. Improved photocatalytic decomposition of aqueous Rhodamine-B by solar light illuminated hierarchical yttria nanosphere decorated ceria nanorods. J. Mater. Res. Technol. 2019, 8, 2898–2909. [Google Scholar] [CrossRef]
  48. Magdalane, C.M.; Kaviyarasu, K.; Matinise, N.; Mayedwa, N.; Mongwaketsi, N.; Letsholathebe, D.; Mola, G.T.; Al-Dhabi, N.A.; Arasu, M.V.; Henini, M.; et al. Evaluation on La2O3 garlanded ceria heterostructured binary metal oxide nanoplates for UV/visible light induced removal of organic dye from urban wastewater. South Afr. J. Chem. Eng. 2018, 26, 49–60. [Google Scholar] [CrossRef]
  49. Sreekanth, T.V.M.; Nagajyothi, P.C.; Reddy, G.R.; Shim, J.; Yoo, K. Urea assisted ceria nanocubes for efficient removal of malachite green organic dye from aqueous system. Sci. Rep. 2019, 9, 1–9. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  50. Ojha, G.P.; Pant, B.; Park, S.-J.; Park, M.; Kim, H.-Y. Synthesis and characterization of reduced graphene oxide decorated with CeO2-doped MnO2 nanorods for supercapacitor applications. J. Colloid Interface Sci. 2017, 494, 338–344. [Google Scholar] [CrossRef]
  51. Poudel, M.B.; Yu, C.; Kim, H.J. Synthesis of conducting bifunctional polyaniline@ Mn-TiO2 nanocomposites for supercapacitor electrode and visible light driven photocatalysis. Catalysts 2020, 10, 546. [Google Scholar] [CrossRef]
  52. Pant, B.; Ojha, G.P.; Kuk, Y.-S.; Kwon, O.H.; Park, Y.W.; Park, M. Synthesis and Characterization of ZnO-TiO2/Carbon Fiber Composite with Enhanced Photocatalytic Properties. Nanomaterials 2020, 10, 1960. [Google Scholar] [CrossRef] [PubMed]
Figure 1. Synthesis scheme of CeO2/CuO nanocomposite.
Figure 1. Synthesis scheme of CeO2/CuO nanocomposite.
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Figure 2. Photocatalytic degradation of methylene blue at of CeO2/CuO nanoparticles.
Figure 2. Photocatalytic degradation of methylene blue at of CeO2/CuO nanoparticles.
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Figure 3. (a) X-ray power diffraction (XRPD) pattern and (b) FTIR spectrum of CeO2-CuO nanocomposite.
Figure 3. (a) X-ray power diffraction (XRPD) pattern and (b) FTIR spectrum of CeO2-CuO nanocomposite.
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Figure 4. SEM images of CeO2-CuO nanocomposite (ac) at different magnification of (a) 5.0 μm, (b) 3.0 μm, and (c) 0.5 μm. (d) EDS Pattern of CeO2-CuO nanocomposite (e) Elemental analysis of EDS pattern of CeO2-CuO nanocomposite
Figure 4. SEM images of CeO2-CuO nanocomposite (ac) at different magnification of (a) 5.0 μm, (b) 3.0 μm, and (c) 0.5 μm. (d) EDS Pattern of CeO2-CuO nanocomposite (e) Elemental analysis of EDS pattern of CeO2-CuO nanocomposite
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Figure 5. (a) UV/Vis spectrum of Cerium nanocomposites (CeO2-CuO) and (b) time-dependent optical absorbance spectra of methylene blue (MB) showing the gradual decrease in concentration with time of CeO2-CuO used as catalyst.
Figure 5. (a) UV/Vis spectrum of Cerium nanocomposites (CeO2-CuO) and (b) time-dependent optical absorbance spectra of methylene blue (MB) showing the gradual decrease in concentration with time of CeO2-CuO used as catalyst.
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Figure 6. (a) Decrease in concentration and % degradation of MB dye with CeO2/CuO and (b) natural logarithms of absorbance of MB plotted as a function of irradiation time (c) standard deviation error bar of CeO2/CuO.
Figure 6. (a) Decrease in concentration and % degradation of MB dye with CeO2/CuO and (b) natural logarithms of absorbance of MB plotted as a function of irradiation time (c) standard deviation error bar of CeO2/CuO.
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Table 1. Comparing catalysts performance of CeO, CuO, and CeO/CuO nanocomposite.
Table 1. Comparing catalysts performance of CeO, CuO, and CeO/CuO nanocomposite.
Sr#Composite NameDye DegradedDose of CatalystDose of DyeTime of DegradationConditionReference
1CeO nanoparticlesMB20 mg/L15 ml9 hVisible light irradiation[45]
2CuO nanoparticlesMB20 mg10 mg/L6 hVisible light irradiation[46]
3CeO/CuO NanocompositeMB1 g/L0.03 mM150 minVisible light irradiationThis work
Table 2. Summary of some reported bimetallic oxides for photocatalytic dye degradation.
Table 2. Summary of some reported bimetallic oxides for photocatalytic dye degradation.
Photocatalyst% EfficiencyDegradation Time (min)References
Y2O3/CeO295.5240[47]
La2O3/CeO270120[48]
Urea/CeO27021[49]
MnO2/CeO290.4[50]
Mn-TiO28924[51]
ZnO-TiO280120[52]
CeO2/CuO85.66150
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Raees, A.; Jamal, M.A.; Ahmed, I.; Silanpaa, M.; Saad Algarni, T. Synthesis and Characterization of CeO2/CuO Nanocomposites for Photocatalytic Degradation of Methylene Blue in Visible Light. Coatings 2021, 11, 305. https://0-doi-org.brum.beds.ac.uk/10.3390/coatings11030305

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Raees A, Jamal MA, Ahmed I, Silanpaa M, Saad Algarni T. Synthesis and Characterization of CeO2/CuO Nanocomposites for Photocatalytic Degradation of Methylene Blue in Visible Light. Coatings. 2021; 11(3):305. https://0-doi-org.brum.beds.ac.uk/10.3390/coatings11030305

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Raees, Alia, Muhammad Asghar Jamal, Ikram Ahmed, Mika Silanpaa, and Tahani Saad Algarni. 2021. "Synthesis and Characterization of CeO2/CuO Nanocomposites for Photocatalytic Degradation of Methylene Blue in Visible Light" Coatings 11, no. 3: 305. https://0-doi-org.brum.beds.ac.uk/10.3390/coatings11030305

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