Electronic\nProperties of Janus TMD WSSe/WX<sub>2</sub> (X = S, Se) Heterostructure\nby External Strain: A Hybrid Functional\nStudy

Harvesting\nsolar energy for artificial photosynthesis is an emerging\nfield in alternative energy research. In this work, the structural,\nelectronic, and optical properties of WX<sub>2</sub> (X = S, Se)/WSSe\nheterostructures were systematically studied. Based on the computation\nresults, these heterostructures outperform the isolated WSSe or WX<sub>2</sub> monolayers in terms of photocatalytic performance. A type-II\nband alignment is present in both of the investigated heterostructures,\nwhich encourages the spatial separation of photogenerated carriers\nand raises the total photocatalytic efficiency. Remarkably, band gap\nalterations in the 0.2–2.0 eV range can be promoted by applying\nstrain-engineering modulation, which allows for well-tuned electrical\nfeatures. Through methodical research, the tunable bandgap and integrated\nelectric field produced by the dipole moment under strain of the WSSe/WX<sub>2</sub> (X = S, Se) heterostructure with various stacking configurations\ncan be utilized as exceptional photocatalysts for water splitting\neven in the presence of infrared light. Our calculation results reveal\nthat 2D WSSe/WX<sub>2</sub> is a promising candidate for electronics,\noptoelectronics, and photocatalytic water-splitting applications.