Reshaping photovoltaic efficiency: Characteristic regulation and future application exploration of GaS/MoTe2 van der Waals heterostructure

In this study, the focus was on the investigation of GaS/MoTe2 van der Waals heterostructures. This investigation was conducted using first-principles methods to examine the effects of doping, electric field, and strain on their electrical and optical properties. The investigation revealed that the lattice parameters of the GaS monolayer and the MoTe2 monolayer are 3.593 Å and 3.560 Å, respectively. The constructed heterostructure lattices exhibited a mismatch of 0.918 %, with the A2 configuration proving the most stable. The energy band structure and density of states of the heterostructure demonstrate the presence of a direct band gap, which is advantageous for photogenerated electron excitation, with the conduction band minimum (CBM) and valence band maximum (VBM) primarily derived from the d orbitals of Mo. The built-in electric field formed between the layers has been shown to promote the separation of electrons and holes, thereby improving the photocatalytic efficiency. The externally applied electric field can change the electronic band structure of the heterostructure, which makes it potential for applications in light-emitting diodes and photodetectors. Thermodynamic property studies show that temperature changes affect free energy, enthalpy, and entropy. Strain can modulate the energy band structure of heterostructures, and heterostructures with B1 and B2 configurations show higher efficiency in light absorption, which has potential applications in optical devices. © 2025