Hybrid Density Functional Study on the Photocatalytic Properties of Two-dimensional g-ZnO Based Heterostructures

Abstract

In this work, graphene-like ZnO (g-ZnO)-based two-dimensional (2D) heterostructures (ZnO/WS2 and ZnO/WSe2) were designed as water-splitting photocatalysts based on the hybrid density functional. The dependence of photocatalytic properties on the rotation angles and biaxial strains were investigated. The bandgaps of ZnO/WS2 and ZnO/WSe2 are not obviously affected by rotation angles but by strains. The ZnO/WS2 heterostructures with appropriate rotation angles and strains are promising visible water-splitting photocatalysts due to their appropriate bandgap for visible absorption, proper band edge alignment, and effective separation of carriers, while the water oxygen process of the ZnO/WSe2 heterostructures is limited by their band edge positions. The findings pave the way to efficient g-ZnO-based 2D visible water-splitting materials.

Rotation Tunable Photocatalytic Properties of ZnO/GaN Heterostructures

“…A series of heterostructures, such as C 2 N/InTe, AlN/WS 2 , MoTe 2 /CrS 2 , GaN/Mg(OH) 2 , MoS 2 /CdS, CdS/C 2 N, CdS/ZnSe, BlueP/Mg(OH) 2 , BiNbO 4 /ZnWO 4 , C 60 /g‐C 3 N 4 , SiC/MoS 2 , and GaN/BlueP, exhibit enhanced photocatalytic performance. Especially, some ZnO monolayer‐based heterostructures are ZnO/MoS 2 , ZnO/WS 2 , ZnO/WSe 2 , ZnO/AlN, and N‐ZnO/g‐C 3 N 4 . Shen and coworkers have applied vertical strain to modulate the photocatalytic activity of ZnO/GeC heterostructure, and our previous work reports that biaxial strain can effectively tune the photocatalytic performance for ZnO/GeC heterostructure.…”

Emerging 2D Materials and Their Van Der Waals Heterostructures

“…The quest for efficient water-splitting photocatalysts motivates the first principle studies by Wang and coworkers [71,72], in which graphene-like carbon nitride, g-C 3 N 4 , and zinc oxide, g-ZnO, are used to form 2D heterojunctions with transition metal (di)chalcogenides. The investigation of CdS/g-C 3 N 4 [71] and g-ZnO/WS 2 [72] heterostructures aims to find appropriate strategies to modulate the electronic and photocatalytic properties of the individual materials.…”

“…The quest for efficient water-splitting photocatalysts motivates the first principle studies by Wang and coworkers [71,72], in which graphene-like carbon nitride, g-C 3 N 4 , and zinc oxide, g-ZnO, are used to form 2D heterojunctions with transition metal (di)chalcogenides. The investigation of CdS/g-C 3 N 4 [71] and g-ZnO/WS 2 [72] heterostructures aims to find appropriate strategies to modulate the electronic and photocatalytic properties of the individual materials. Indeed, both cadmium sulfide CdS [73] and graphitic carbon nitride g-C 3 N 4 [74] have suitable bandgaps for visible light absorption (2.4 and 2.7 eV, respectively) and could be good photocatalysts, but the former lacks stability due to the self-oxidation of photogenerated species while the latter has poor photocatalytic efficiency because of the fast recombination of photogenerated electron-hole pairs.…”

“…The water-splitting photocatalytic properties of the heterostructures formed by g-ZnO with two-dimensional WS 2 or WSe 2 are studied as a function of the rotation angles and the biaxial strain [72] as well. g-ZnO has been experimentally synthesized [75] and density functional theory studies have suggested that doping with nonmetal species can endow it with tunable magnetism [76].…”

Tuning Photocatalytic Performance of Multilayer ZnO for Water Splitting by Biaxial Strain Composites

“…Due to the significant influence of interlayer interaction and the quantum confinement effect on the energy band structure of the material, 2D multilayer structure material often has unique electronic characteristics, and it has gradually become a new research hotspot in the field of photocatalysis [11][12][13][14][15][16][17][18][19][20]. Meanwhile, research studies on their 2D structures are also proceeding rapidly and productively, ever since the successful experimental synthesis of their graphene-like 2D counterparts.…”