MoSSe nanotube: a promising photocatalyst with an extremely long carrier lifetime

Abstract

Semiconductor-based photocatalysts for hydrogen production have been considered as one of the most promising solutions to the current worldwide energy crisis. However, the low solar energy utilization efficiency and the high photogenerated electron–hole recombination rate limit their applications severely. Here, based on the time-dependent density functional theory and nonadiabatic molecular dynamics, we propose that one-dimensional Janus MoSSe nanotube is a promising photocatalyst with high catalytic efficiency. Our results show that the Janus MoSSe nanotube prossesses suitable direct band-gaps and appropriate band edge positions that perfectly meet the requirements of water redox reactions. In particular, it exhibits pronounced optical absorption in the visible region of the solar spectrum. Most importantly, due to the built-in electric field, an ultra-long carrier lifetime of 33 ns has been observed, which is comparable to that of TiO₂. Such extremely long carrier lifetime can efficiently reduce the recombination rate of photogenerated electrons and holes, leading to high solar energy conversion efficiency. These advanced properties make the Janus MoSSe nanotube a promising candidate for further water splitting applications.