Computational investigation unveiling strain-engineered enhancements in the 2D InP photocatalyst for hydrogen production efficiency

Solar-driven water splitting for hydrogen production is considered a promising and sustainable solution to address both environmental challenges and the ongoing energy crisis. In this context, extensive research has been dedicated to developing photocatalysts that meet the requirements for efficient water splitting, as well as to gaining a deeper understanding of the photocatalytic process. In this study, we explore the potential of two-dimensional (2D) indium phosphide (InP) nanosheets as an efficient photocatalyst for hydrogen production (H2) under strain effects, using density functional theory (DFT) calculations. Our results show that 2D InP nanosheets exhibit an optimal bandgap of 2.32 eV, as determined using the HSE06 functional. Furthermore, significant improvements were observed in the optical, electronic, and photocatalytic properties when biaxial strain was applied. The absorption coefficient demonstrates enhanced visible light absorption of 58.23 × 10⁴/cm at −6 % strain, corresponding to a bandgap of 3.08 eV. Additionally, hydrogen production is significantly improved under biaxial tensile strain, reaching a value of 15.96 μmol/g at +6 % strain. These findings suggest that InP nanosheets under tensile strain could be promising candidates for the development of efficient photocathodes for hydrogen production.