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As a green technology, photocatalytic reduction of CO2 can reduce CO2 into reusable carbon‐based fuels and alleviate environmental and energy problems to a certain extent. However, traditional photocatalytic materials have irreparable defects that limit their applications in photocatalysis, and it becomes a great challenge to find an efficient photocatalytic material. ZnIn2S4, a new photocatalyst, is widely used in photocatalysis because of its layered structure, tunable band gap, excellent photoelectric properties, and catalytic characteristics, and it is also favored by a wide range of scientific researchers due to its stable chemical properties. The construction of heterojunctions can further increase the photocatalytic ability of ZnIn2S4. This review introduces the electron transfer mechanism of different ZnIn2S4‐based heterojunctions in the photocatalytic process and its recent research progress in photocatalytic CO2 reduction applications. Finally, an outlook on constructing ZnIn2S4‐based heterojunctions and their development prospects is presented. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) heterostructures formed by van der Waals (vdW) interactions have attracted considerable attention in the fields of electronics and optoelectronics. The stacking order is not only an important method for regulating interlayer interactions, but also an intrinsic property specific to 2D vdW heterostructures. Herein, the GaS/XMoY (X/Y = S, Se, Te) vdW heterostructures are proposed by first-principles calculations. The effects of stacking order (namely, GaS/SMoSe, GaS/SeMoS, GaS/SeMoTe and GaS/TeMoSe) on the electronic properties, light absorption, and photocatalysis of the heterostructures are discussed in detail. We identify stacking order as a dominant pathway for interlayer interactions, and surmise that stacking order effectively regulates dipole moment, mechanical flexibility, carrier mobility, optical absorption coefficient, and photocatalytic water-splitting of GaS/XMoY heterostructures. The in-plane biaxial strain can make the energy gap of each stacking order reach a maximum value, and their photocatalytic performance can also be improved to different degrees. This work analyzes the modulation effect of stacking order on the material properties of GaS/XMoY heterostructures, which provides theoretical clues for the design of efficient and stable optoelectronic devices and photocatalytic water-splitting. [ABSTRACT FROM AUTHOR]

Abstract The transition metal dichalcogenides (TMDCs) have drawn considerable attention because their unique application in novel quantum optoelectronic devices. Here, we design the MoS 2 -like Janus InSeF film and stacked two different layers to form hereostructures. The first principles study results show that F bonds to In, with the atoms in the sequence of F-In-Se-Se-In-F. The calculated band structures shows a semiconducting character with a gap of 0.58 eV. The band gap is sensitive to strains, varied from 0 to 1.23 eV. Remarkably, this film can turn from a normal insulator to topological insulator (TI) under appropriate compressive strain. Also, we find a direct-to-indirect band gap transition, if the tensile strain growing. These results mean that it provides an ideal platform to realize low-dissipation quantum and spintronic devices based on InSeF films. Highlights • Two dimensional InSeF hereostructures are studied. • The topological states are triggered by s-p xy band inversion when compressive strains applied. • A direct-to-indirect band gap transition occurred when tensile strain growing. [ABSTRACT FROM AUTHOR]

Abstract A new hydrogenated amorphous silicon carbide (a-SiC x :H) thin film with carbon nanostructure is grown through plasma enhanced chemical vapor deposition (PECVD) method. The structural evolution and growth mechanism of the as deposited a-SiC x :H thin film are explored and further discussed with different substrate temperatures. The results show that the structure of the a-SiC x :H thin film is a multiphase structure of carbon nanostructures embedded into C Si O(H) amorphous matrix, and the carbon nanostructure is a spheroidal graphite-like structure. With increasing substrate temperature, the carbon nanostructure gradually grows up through incorporation with surrounding nanostructures. When the substrate temperature increases further to 300 °C, the ultrafine basic structure units of graphite are found within the carbon nanostructure. In addition, the disorder of the thin film first increases and then decreases with increasing substrate temperature, which give rise to band tail states among the π-π⁎ band gap. The change of structure of as synthesized a-SiC x :H thin film with different substrate temperatures supports the sub-plantation model. Furthermore, a tunable optical band gap depended on structure of the carbon nanostructures is demonstrated at different substrate temperatures, which may bring about a potential of application. Highlights • A new a-SiC x :H film with carbon nanostructures are synthesized by PECVD method. • The carbon nanostructure is a spheroidal graphite-like structure. • The size of the nanostructures increases with increasing substrate temperature. • The formation mechanism of nanostructures supports the sub-plantation model. [ABSTRACT FROM AUTHOR]

Opening a sizable band gap in the zero-gap silicene is a key issue for its application in nanoelectronics. We design new 2D silicene and GaP heterobilayer (Si/GaP HBL) composed of silicene and monolayer (ML) GaP. Based on first-principles calculations, we find that the interaction energies are in the range of −295.5 to −297.5 meV per unit cell, indicating a weak interaction between silicene and gallium phosphide (GaP) monolayer. The band gap changes ranging from 0.06 to 0.44 eV in hybrid HBLs. An unexpected indirect–direct band gap crossover is also observed in HBLs, dependent on the stacking pattern. These provide a possible way to design effective FETs out of silicene on GaP monolayer. [ABSTRACT FROM AUTHOR]