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 (TlAsS 2 ) can be experimentally synthesized due to its low cleavage energy (0.33 J/m 2 ) and high stability. Notably, TlAsS 2 possesses suitable electronegativity (5.06 eV) and a band gap of 2.56 eV, making it a viable candidate for PWS devices. Additionally, the single-layer exhibits an impressive electron mobility of 209.83–600.14 cm 2 /Vs, much higher than the hole mobility of 42.07–52.02 cm 2 /Vs. Also, it demonstrates a strong absorption coefficient (~10 5 cm −1 ), effectively covering both visible and ultraviolet light, resulting in a desirable light absorption efficiency of 39 %. In conclusion, single-layer TlAsS 2 is a highly promising candidate for optoelectronic and PWS applications due to its favorable electronic properties, light absorption capabilities and overall PWS efficiency. • Single-layer TlAsS 2 exhibits low cleavage energy (0.33 J/m 2 ) alongside high stability, making it suitable for experimental synthesis. • It possesses suitable band edges for photocatalytic water splitting devices. • Single-layer displays desirable solar-to-hydrogen efficiency of 9%.