NH3-treated MoS2 nanosheets as photocatalysts for enhanced H2 evolution under visible-light irradiation

Abstract

MoS2 is widely applied in photocatalytic H2 evolution to function as an efficient cocatalyst, whereas it is not yet reported that this material acted as an effective host photocatalyst in this field. Herein, MoS2 nanosheets were prepared by a general hydrothermal process at first, and then treated with flowing NH3 at temperatures from 400 to 900 °C to develop a series of novel MoS2-based photocatalysts, which showed considerable photocatalytic activities for H2 evolution under visible-light irradiation. It was deduced from different instrumental characterizations on the physicochemical properties of photocatalysts that the enhancement of photocatalytic activity by high-temperature NH3 treatment could be mainly attributed to the modification of surface properties (such as electric property and acid-base properties) by N, which promoted the adsorption of reactants and further accelerated photocatalytic reaction. This work presented an effective route to explore new H2-evolution photocatalysts by modifying the appropriate materials that were commonly employed as cocatalysts.