Research

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11 pages, 3608 KiB

Open AccessArticle

Construction of the Heterostructure of NiPt Truncated Octahedral Nanoparticle/MoS₂ and Its Interfacial Structure Evolution

by Congyan Mu, Hao Li, Liang Zhou, Huanyu Ye, Rongming Wang and Yinghui Sun

Nanomaterials 2023, 13(11), 1777; https://0-doi-org.brum.beds.ac.uk/10.3390/nano13111777 - 31 May 2023

Viewed by 973

Abstract

Interfacial atomic configuration plays a vital role in the structural stability and functionality of nanocomposites composed of metal nanoparticles (NPs) and two−dimensional semiconductors. In situ transmission electron microscope (TEM) provides a real−time technique to observe the interface structure at atomic resolution. Herein, we [...] Read more.

Interfacial atomic configuration plays a vital role in the structural stability and functionality of nanocomposites composed of metal nanoparticles (NPs) and two−dimensional semiconductors. In situ transmission electron microscope (TEM) provides a real−time technique to observe the interface structure at atomic resolution. Herein, we loaded bimetallic NiPt truncated octahedral NPs (TONPs) on MoS₂ nanosheets and constructed a NiPt TONPs/MoS₂ heterostructure. The interfacial structure evolution of NiPt TONPs on MoS₂ was in situ investigated using aberration−corrected TEM. It was observed that some NiPt TONPs exhibited lattice matching with MoS₂ and displayed remarkable stability under electron beam irradiation. Intriguingly, the rotation of an individual NiPt TONP can be triggered by the electron beam to match the MoS₂ lattice underneath. Furthermore, the coalescence kinetics of NiPt TONPs can be quantitatively described by the relationship between neck radius (r) and time (t), expressed as rⁿ = Kt. Our work offers a detailed analysis of the lattice alignment relationship of NiPt TONPs on MoS₂, which may enlighten the design and preparation of stable bimetallic metal NPs/MoS₂ heterostructures. Full article

(This article belongs to the Special Issue State-of-the-Art of Nanocomposite Materials in China)

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14 pages, 3197 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Nonmetallic Active Sites on Nickel Phosphide in Oxygen Evolution Reaction

by Pengfei Zhang, Hongmei Qiu, Huicong Li, Jiangang He, Yingying Xu and Rongming Wang

Nanomaterials 2022, 12(7), 1130; https://0-doi-org.brum.beds.ac.uk/10.3390/nano12071130 - 29 Mar 2022

Cited by 3 | Viewed by 2050

Abstract

Efficient and durable catalysts are crucial for the oxygen evolution reaction (OER). The discovery of the high OER catalytic activity in Ni₁₂P₅ has attracted a great deal of attention recently. Herein, the microscopic mechanism of OER on the surface of [...] Read more.

Efficient and durable catalysts are crucial for the oxygen evolution reaction (OER). The discovery of the high OER catalytic activity in Ni₁₂P₅ has attracted a great deal of attention recently. Herein, the microscopic mechanism of OER on the surface of Ni₁₂P₅ is studied using density functional theory calculations (DFT) and ab initio molecular dynamics simulation (AIMD). Our results demonstrate that the H₂O molecule is preferentially adsorbed on the P atom instead of on the Ni atom, indicating that the nonmetallic P atom is the active site of the OER reaction. AIMD simulations show that the dissociation of H from the H₂O molecule takes place in steps; the hydrogen bond changes from O^a-H⋯O^b to O^a⋯H-O^b, then the hydrogen bond breaks and an H⁺ is dissociated. In the OER reaction on nickel phosphides, the rate-determining step is the formation of the OOH group and the overpotential of Ni₁₂P₅ is the lowest, thus showing enhanced catalytic activity over other nickel phosphides. Moreover, we found that the charge of Ni and P sites has a linear relationship with the adsorption energy of OH and O, which can be utilized to optimize the OER catalyst. Full article

(This article belongs to the Special Issue State-of-the-Art of Nanocomposite Materials in China)

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11 pages, 2743 KiB

Open AccessArticle

Hydrothermal Synthesis of Hierarchical SnO₂ Nanostructures for Improved Formaldehyde Gas Sensing

by Pengyu Ren, Lingling Qi, Kairui You and Qingwei Shi

Nanomaterials 2022, 12(2), 228; https://0-doi-org.brum.beds.ac.uk/10.3390/nano12020228 - 11 Jan 2022

Cited by 30 | Viewed by 2537

Abstract

The indoor environment of buildings affects people’s daily life. Indoor harmful gases include volatile organic gas and greenhouse gas. Therefore, the detection of harmful gas by gas sensors is a key method for developing green buildings. The reasonable design of SnO₂-sensing [...] Read more.

The indoor environment of buildings affects people’s daily life. Indoor harmful gases include volatile organic gas and greenhouse gas. Therefore, the detection of harmful gas by gas sensors is a key method for developing green buildings. The reasonable design of SnO₂-sensing materials with excellent structures is an ideal choice for gas sensors. In this study, three types of hierarchical SnO₂ microspheres assembled with one-dimensional nanorods, including urchin-like microspheres (SN-1), flower-like microspheres (SN-2), and hydrangea-like microspheres (SN-3), are prepared by a simple hydrothermal method and further applied as gas-sensing materials for an indoor formaldehyde (HCHO) gas-sensing test. The SN-1 sample-based gas sensor demonstrates improved HCHO gas-sensing performance, especially demonstrating greater sensor responses and faster response/recovery speeds than SN-2- and SN-3-based gas sensors. The improved HCHO gas-sensing properties could be mainly attributed to the structural difference of smaller nanorods. These results further indicate the uniqueness of the structure of the SN-1 sample and its suitability as HCHO- sensing material. Full article

(This article belongs to the Special Issue State-of-the-Art of Nanocomposite Materials in China)

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12 pages, 3586 KiB

Open AccessArticle

A Novel Long Short-Term Memory Based Optimal Strategy for Bio-Inspired Material Design

by Bin Ding, Dong Li and Yuli Chen

Nanomaterials 2021, 11(6), 1389; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11061389 - 25 May 2021

Cited by 4 | Viewed by 1908

Abstract

Biological materials have attracted a lot of attention due to their simultaneous superior stiffness and toughness, which are conventionally attributed to their staggered structure (also known as brick and mortar) at the most elementary nanoscale level and self-similar hierarchy at the overall level. [...] Read more.

Biological materials have attracted a lot of attention due to their simultaneous superior stiffness and toughness, which are conventionally attributed to their staggered structure (also known as brick and mortar) at the most elementary nanoscale level and self-similar hierarchy at the overall level. Numerous theoretical, numerical, and experimental studies have been conducted to determine the mechanism behind the load-bearing capacity of the staggered structure, while few studies focus on whether the staggered structure is globally optimal in the entire design space at the nanoscale level. Here, from the view of structural optimization, we develop a novel long short-term memory (LSTM) based iterative strategy for optimal design to demonstrate the simultaneous best stiffness and toughness of the staggered structure. Our strategy is capable of both rapid discovery and high accuracy based on less than 10% of the entire design space. Besides, our strategy could obtain and maintain all of the best sample configurations during iterations, which can hardly be done by the convolutional neural network (CNN)-based optimal strategy. Moreover, we discuss the possible future material design based on the failure point of the staggered structure. The LSTM-based optimal design strategy is general and universal, and it may be employed in many other mechanical and material design fields with the premise of conservation of mass and multiple optimal sample configurations. Full article

(This article belongs to the Special Issue State-of-the-Art of Nanocomposite Materials in China)

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10 pages, 10669 KiB

Open AccessArticle

Influence of the Interface Composition to the Superconductivity of Ti/PdAu Films

by Xiaolong Xu, Mauro Rajteri, Jinjin Li, Shuo Zhang, Jian Chen, Eugenio Monticone, Qing Zhong, Huifang Gao, Wei Li, Xu Li, Qi Li, Yuan Zhong, Wenhui Cao, Shijian Wang, Ying Gao, Zheng Liu and Xueshen Wang

Nanomaterials 2021, 11(1), 39; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11010039 - 25 Dec 2020

Cited by 3 | Viewed by 2237

Abstract

In this work, the interface composition of the superconducting Ti/PdAu bilayer is tuned by an annealing process in N₂ from 100 to 500 °C to control the superconducting transition temperature (T_c). This Ti-PdAu composition layer is characterized with a [...] Read more.

In this work, the interface composition of the superconducting Ti/PdAu bilayer is tuned by an annealing process in N₂ from 100 to 500 °C to control the superconducting transition temperature (T_c). This Ti-PdAu composition layer is characterized with a high-resolution transmission electron microscopy (HRTEM) and energy-dispersive spectrometer (EDS) to show the infiltration process. The surface topography, electrical, and cryogenic properties are also shown. The inter-infiltration of Ti and PdAu induced by the thermal treatments generates an intermixed layer at the interface of the bilayer film. Due to the enforced proximity effect by the annealing process, the T_c of Ti (55 nm)/PdAu (60 nm) bilayer thin films is tuned from an initial value of 243 to 111 mK which is a temperature that is suitable for the application as the function unit of a superconducting transition edge sensor. Full article

(This article belongs to the Special Issue State-of-the-Art of Nanocomposite Materials in China)

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Review

Jump to: Research

26 pages, 6499 KiB

Open AccessReview

Optimization Methods of Tungsten Oxide-Based Nanostructures as Electrocatalysts for Water Splitting

by Yange Wang, Rongming Wang and Sibin Duan

Nanomaterials 2023, 13(11), 1727; https://0-doi-org.brum.beds.ac.uk/10.3390/nano13111727 - 25 May 2023

Cited by 2 | Viewed by 1753

Abstract

Electrocatalytic water splitting, as a sustainable, pollution-free and convenient method of hydrogen production, has attracted the attention of researchers. However, due to the high reaction barrier and slow four-electron transfer process, it is necessary to develop and design efficient electrocatalysts to promote electron [...] Read more.

Electrocatalytic water splitting, as a sustainable, pollution-free and convenient method of hydrogen production, has attracted the attention of researchers. However, due to the high reaction barrier and slow four-electron transfer process, it is necessary to develop and design efficient electrocatalysts to promote electron transfer and improve reaction kinetics. Tungsten oxide-based nanomaterials have received extensive attention due to their great potential in energy-related and environmental catalysis. To maximize the catalytic efficiency of catalysts in practical applications, it is essential to further understand the structure–property relationship of tungsten oxide-based nanomaterials by controlling the surface/interface structure. In this review, recent methods to enhance the catalytic activities of tungsten oxide-based nanomaterials are reviewed, which are classified into four strategies: morphology regulation, phase control, defect engineering, and heterostructure construction. The structure–property relationship of tungsten oxide-based nanomaterials affected by various strategies is discussed with examples. Finally, the development prospects and challenges in tungsten oxide-based nanomaterials are discussed in the conclusion. We believe that this review provides guidance for researchers to develop more promising electrocatalysts for water splitting. Full article

(This article belongs to the Special Issue State-of-the-Art of Nanocomposite Materials in China)

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14 pages, 2610 KiB

Open AccessReview

Recent Progress in Two-Dimensional MoTe₂ Hetero-Phase Homojunctions

by Jing Guo and Kai Liu

Nanomaterials 2022, 12(1), 110; https://0-doi-org.brum.beds.ac.uk/10.3390/nano12010110 - 30 Dec 2021

Cited by 7 | Viewed by 4933

Abstract

With the demand for low contact resistance and a clean interface in high-performance field-effect transistors, two-dimensional (2D) hetero-phase homojunctions, which comprise a semiconducting phase of a material as the channel and a metallic phase of the material as electrodes, have attracted growing attention [...] Read more.

With the demand for low contact resistance and a clean interface in high-performance field-effect transistors, two-dimensional (2D) hetero-phase homojunctions, which comprise a semiconducting phase of a material as the channel and a metallic phase of the material as electrodes, have attracted growing attention in recent years. In particular, MoTe₂ exhibits intriguing properties and its phase is easily altered from semiconducting 2H to metallic 1T′ and vice versa, owing to the extremely small energy barrier between these two phases. MoTe₂ thus finds potential applications in electronics as a representative 2D material with multiple phases. In this review, we briefly summarize recent progress in 2D MoTe₂ hetero-phase homojunctions. We first introduce the properties of the diverse phases of MoTe₂, demonstrate the approaches to the construction of 2D MoTe₂ hetero-phase homojunctions, and then show the applications of the homojunctions. Lastly, we discuss the prospects and challenges in this research field. Full article

(This article belongs to the Special Issue State-of-the-Art of Nanocomposite Materials in China)

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18 pages, 5145 KiB

Open AccessReview

Morphology-Dependent Room-Temperature Ferromagnetism in Undoped ZnO Nanostructures

by Hongtao Ren and Gang Xiang

Nanomaterials 2021, 11(12), 3199; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11123199 - 25 Nov 2021

Cited by 11 | Viewed by 2250

Abstract

Since Dietl et al. predicted that Co-doped ZnO may show room-temperature ferromagnetism (RTFM) in 2000, researchers have focused on the investigation of ferromagnetic ZnO doped with various transition metals. However, after decades of exploration, it has been found that undoped ZnO nanostructures can [...] Read more.

Since Dietl et al. predicted that Co-doped ZnO may show room-temperature ferromagnetism (RTFM) in 2000, researchers have focused on the investigation of ferromagnetic ZnO doped with various transition metals. However, after decades of exploration, it has been found that undoped ZnO nanostructures can also show RTFM, which in general is dependent on ZnO morphologies. Here, we will give an overall review on undoped ZnO nanomaterials with RTFM. The advanced strategies to achieve multidimensional (quasi-0D, 1D, 2D, and 3D) ferromagnetic ZnO nanostructures and the mechanisms behind RTFM are systematically presented. We have successfully prepared ferromagnetic nanostructures, including thin films, horizontal arrays and vertical arrays. The existing challenges, including open questions about quantum-bound ZnO nanostructures, are then discussed. Full article

(This article belongs to the Special Issue State-of-the-Art of Nanocomposite Materials in China)

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