Two-dimensional Lorandite with high-efficiency photocatalytic water splitting: Insights from ab initio calculations

Photocatalytic water splitting (PWS) plays a crucial role in clean energy generation and environmental protection. In this study, we identified that single-layer Lorandite (TlAsS₂) can be experimentally synthesized due to its low cleavage energy (0.33 J/m²) and high stability. Notably, TlAsS₂ possesses suitable electronegativity (5.06 eV) and a band gap of 2.56 eV, making it a viable candidate for PWS devices. Additionally, single-layer exhibits an electron mobility of 209.83–600.14 cm²/Vs, much higher than the hole mobility of 42.07–52.02 cm²/Vs. Also, it demonstrates a strong absorption coefficient (∼10⁵ cm⁻¹), effectively covering both visible and ultraviolet light, resulting in a desirable light absorption efficiency of 39 %. In conclusion, single-layer TlAsS₂ is a highly promising candidate for optoelectronic and PWS applications due to its favorable electronic properties, light absorption capabilities and overall PWS efficiency.