Electronic properties and enhanced photocatalytic performance of van der Waals heterostructures of ZnO and Janus transition metal dichalcogenides

Abstract

Vertical stacking of two-dimensional materials into layered van der Waals heterostructures has recently been considered as a promising candidate for photocatalytic and optoelectronic devices because it can combine the advantages of the individual 2D materials.

Intriguing electronic structure and photocatalytic performance of blueP–SMSe and blueP–SeMS (M = Mo, W) van der Waals heterostructures

“…This trend has been found in MoSSe-WSSe, GeC/Janus-TMDCs, ZnO/Janus-TMDCs, and SiC-TMDCs. [33][34][35] Apparently, photogenerated electrons will transfer from blueP to SMoSe, SWSe and holes will move in the opposite direction from SMoSe, SWSe to blueP, this mechanism will minimize the rate of combination of charge. Hence, blueP-SMoSe, blueP-SWSe heterostructures must be thoroughly considered for applications in solar cells.…”

“…This clearly shows a weak interaction between blueP and the SMSe monolayers; this characteristic has also been shown by GeC-Janus-TMDCs and ZnO-Janus-TMDCs. 34,35 The production of hydrogen gas under solar irradiation using a photocatalyst is in high demand for safe and environment friendly renewable energy sources. In general, the oxidation and reduction reaction for photocatalytic water splitting can be written as: E OX O2=H2O ¼ À5:67 eV þ pH Â 0:059 eV and E red H þ =H2 ¼ 4:44 eV þ pH Â 0:059 eV.…”

“…A similar trend has also been demonstrated in GeC-Janus-TMDCs and ZnO-Janus-TMDCs heterobilayers. 34,35 In contrast, P-SMoSe is not capable to perform the reduction reaction and is suitable for the oxidation reaction, as displayed in Fig. 6.…”

“…Theoretical ndings have revealed type-II band alignment with enhanced optoelectronic, spintronic and photocatalytic water splitting behavior in MoSSe/ WSSe, GeC/Janus-TMDC and ZnO/Janus-TMDC heterostructures. [33][34][35] In view of the above remarkable properties and acceptable lattice mismatch of blueP and Janus SMSe and SeMS (M ¼ Mo, W) monolayers, the intriguing physical properties of the blueP-SMSe and blueP-SeMS (M ¼ Mo, W) vdW stacking are investigated by rst principles studies. In the present work, two different models of vdW heterostructures are formed with interchanging positions of the chalcogen atoms at the lower/top layers of the Janus monolayer.…”

Van der Waals heterostructures of SiC and Janus MSSe (M = Mo, W) monolayers: a first principles study

“…5 To overcome this issue, layer stacking in the form of van der Waals (vdW) heterostructures with localization of the valence band maximum (VBM) and conduction band minimum (CBM) to two different layers (type-II) is intensively used in designing viable electronic products. [6][7][8][9][10][11][12][13][14] The SiC monolayer in a planar geometry is a semiconductor with large in-plane stiffness, high carrier mobility and strong thermal stability. It has a hexagonal lattice and satisfying mismatch with MSSe (M ¼ Mo, W) monolayers (less than 2%), hence the fabrication of SiC-MSSe (M ¼ Mo, W) vdW heterostructures can be realized.…”