First-principles study of the photocatalytic properties of CdS/In 2 Te 3 heterostructure

Utilising first-principles calculations, the geometric structure, electronic properties, and photocatalytic characteristics of the CdS/In2Te3 heterostructure have been systematically investigated. The constructed heterostructure displays a Type-II band configuration with a reduced band gap of 1.015 eV, which broadens the light-harvesting range from the visible to the near-infrared region. The differential charge density forms an interfacial electric field oriented from In2Te3 to CdS, which enhances the efficient separation and directional migration of photogenerated carriers. The spectrum of optical absorption exhibits a significant enhancement in the near-infrared region, indicating superior light-harvesting capability compared to that of single-component monolayers. Band edge analysis supports the thermodynamic feasibility of water splitting, and the theoretical solar-to-hydrogen (STH) efficiency is calculated at 28.2%, significantly higher than that of CdS and In2Te3 monolayers. The work of this paper provides a theoretical method for the development of efficient and stable infrared-driven two-dimensional photocatalysts and is conducive to improving the efficiency of solar hydrogen production.