Self-water-absorption-type two-dimensional composite photocatalyst with high-efficiency water absorption and overall water-splitting performance

Photocatalytic overall water splitting is an interesting research topic in the field of energy and outer space exploration. Here, we designed a P/MoS2 composite photocatalyst with self-water-absorption performance by compositing MoS2 nanosheets and polycrystalline black phosphorus nanosheets. The composite photocatalyst produced a sufficient amount of hydrogen in the absence of any precious metal. This also demonstrated photocatalytic overall water-splitting ability in the absence of any sacrificial agent. More interestingly, it effectively absorbed water and demonstrated good overall water-splitting performance under the simulated Mars conditions; the average hydrogen production rate was 17.68 ​μmol ​h−1 ​g−1, and the oxygen production rate was 7.61 ​μmol ​h−1 ​g−1 over a period of 70 ​h. A comprehensive investigation of the ability of the composite photocatalyst to absorb water and produce hydrogen was performed.