共查询到20条相似文献，搜索用时 15 毫秒
1.
2.
3.
4.
Juqing Liu Zhiyuan Zeng Xiehong Cao Gang Lu Lian‐Hui Wang Qu‐Li Fan Wei Huang Hua Zhang 《Small (Weinheim an der Bergstrasse, Germany)》2012,8(22):3517-3522
A facile method for exfoliation and dispersion of molybdenum disulfide (MoS2) with the aid of polyvinylpyrrolidone (PVP) is proposed. The resultant PVP‐coated MoS2 nanosheets, i.e., MoS2‐PVP nanocomposites, are well dispersed in the low‐boiling ethanol solvent, facilitating their thin film preparation and the device fabrication by solution processing technique. As a proof of concept, a flexible memory diode with the configuration of reduced graphene oxide (rGO)/MoS2‐PVP/Al exhibited a typical bistable electrical switching and nonvolatile rewritable memory effect with the function of flash. These experimental results prove that the electrical transition is due to the charge trapping and detrapping behavior of MoS2 in the PVP dielectric material. This study paves a way of employing two‐dimensional nanomaterials as both functional materials and conducting electrodes for the future flexible data storage. 相似文献
5.
6.
Naguib M Kurtoglu M Presser V Lu J Niu J Heon M Hultman L Gogotsi Y Barsoum MW 《Advanced materials (Deerfield Beach, Fla.)》2011,23(37):4248-4253
7.
8.
9.
10.
Qin Liu Xiuling Li Qun He Adnan Khalil Daobin Liu Ting Xiang Xiaojun Wu Li Song 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(41):5556-5564
Most recently, much attention has been devoted to 1T phase MoS2 because of its distinctive phase‐engineering nature and promising applications in catalysts, electronics, and energy storage devices. While alkali metal intercalation and exfoliation methods have been well developed to realize unstable 1T‐MoS2, but the aqueous synthesis for producing stable metallic phase remains big challenging. Herein, a new synthetic protocol is developed to mass‐produce colloidal metallic 1T‐MoS2 layers highly stabilized by intercalated ammonium ions (abbreviated as N‐MoS2). In combination with density functional calculations, the X‐ray diffraction pattern and Raman spectra elucidate the excellent stability of metallic phase. As clearly depicted by high‐angle annular dark‐field imaging in an aberration‐corrected scanning transmission electron microscope and extended X‐ray absorption fine structure, the N‐MoS2 exhibits a distorted octahedral structure with a 2a 0 × a 0 basal plane superlattice and 2.72 Å Mo–Mo bond length. In a proof‐of‐concept demonstration for the obtained material's applications, highly efficient photocatalytic activity is achieved by simply hybridizing metallic N‐MoS2 with semiconducting CdS nanorods due to the synergistic effect. As a direct outcome, this CdS:N‐MoS2 hybrid shows giant enhancement of hydrogen evolution rate, which is almost 21‐fold higher than pure CdS and threefold higher than corresponding annealed CdS:2H‐MoS2. 相似文献
11.
12.
13.
Zhikun Zheng Ronny Grünker Xinliang Feng 《Advanced materials (Deerfield Beach, Fla.)》2016,28(31):6529-6545
Microporous membranes act as selective barriers and play an important role in industrial gas separation and water purification. The permeability of such membranes is inversely proportional to their thickness. Synthetic two‐dimensional materials (2DMs), with a thickness of one to a few atoms or monomer units are ideal candidates for developing separation membranes. Here, groundbreaking advances in the design, synthesis, processing, and application of 2DMs for gas and ion separations, as well as water desalination are presented. This report describes the syntheses, structures, and mechanical properties of 2DMs. The established methods for processing 2DMs into selective permeation membranes are also discussed and the separation mechanism and their performances addressed. Current challenges and emerging research directions, which need to be addressed for developing next‐generation separation membranes, are summarized. 相似文献
14.
Halide perovskites have high light absorption coefficients, long charge carrier diffusion lengths, intense photoluminescence, and slow rates of non‐radiative charge recombination. Thus, they are attractive photoactive materials for developing high‐performance optoelectronic devices. These devices are also cheap and easy to be fabricated. To realize the optimal performances of halide perovskite‐based optoelectronic devices (HPODs), perovskite photoactive layers should work effectively with other functional materials such as electrodes, interfacial layers and encapsulating films. Conventional two‐dimensional (2D) materials are promising candidates for this purpose because of their unique structures and/or interesting optoelectronic properties. Here, we comprehensively summarize the recent advancements in the applications of conventional 2D materials for halide perovskite‐based photodetectors, solar cells and light‐emitting diodes. The examples of these 2D materials are graphene and its derivatives, mono‐ and few‐layer transition metal dichalcogenides (TMDs), graphdiyne and metal nanosheets, etc. The research related to 2D nanostructured perovskites and 2D Ruddlesden–Popper perovskites as efficient and stable photoactive layers is also outlined. The syntheses, functions and working mechanisms of relevant 2D materials are introduced, and the challenges to achieving practical applications of HPODs using 2D materials are also discussed. 相似文献
15.
16.
Qingsheng Zeng Hong Wang Wei Fu Yongji Gong Wu Zhou Pulickel M. Ajayan Jun Lou Zheng Liu 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(16):1868-1884
The discovery of graphene has sparked much interest in science and lead to the development of an ample variety of novel two‐dimensional (2D) materials. With increasing research interest in the field of 2D materials in recent years, the researchers have shifted their focus from the synthesis to the modification of 2D materials, emphasizing their electronic structures. In this review, the possibilities of altering the band structures are discussed via three different approches: (1) alloying 2D materials, so called ternary 2D materials, such as hexagonal carbonized boron nitrides (h‐BCN) and transition metal dichalcogenides (TMDs) ternary materials; (2) stacking 2D materials vertically, which results in 2D heterostructures named van der Waals (vdW) solids (using hexagonal boron nitrides (h‐BN)/graphene and TMDs stacking as examples), and growing lateral TMDs heterostructrues; (3) controlling the thickness of 2D materials, that is, the number of layers. The electronic properties of some 2D materials are very sensitive to the thickness, such as in TMDs and black phosphorus (BP). The variations of band structures and the resulting physical properties are systematically discussed. 相似文献
17.
18.
19.
20.
《Advanced Materials Interfaces》2017,4(16)
The heterostructure of 2D material with different orientations and TiO2 has been proven to be a good candidate for photocatalytic water splitting. However, the detailed mechanism of the orientation of 2D materials with TiO2 has not been explored. Herein, different combinations of edge‐on MoS2 or basal‐on MoS2 with TiO2 are investigated systematically. The adsorption energy, the activation energy barrier, as well as the charge distribution reveal that edge‐on heterostructures have better efficiency in the separation of photoelectron–hole pairs and can enhance the efficiency of hydrogen evolution reaction. This work studies the differences in mechanisms of edge‐on and basal‐on heterostructures in hydrogen evolution reactions. The simulated results provide significant theoretical foundation for the design of new materials. 相似文献