In-situ ion-exchange synthesis AgS modified SnS nanosheets toward highly photocurrent response and photocatalytic activity.

Heterojunction photocatalyst systems are deemed to be an excellent option to improve the photocatalytic behavior of a material. In this paper, AgS/SnS heterojunction photocatalysts were prepared by a simple in-situ ion exchange method from SnS nanosheets. The AgS/SnS composite photoanode exhibits 13.99 μA/cm photocurrent density at 0.7 V (vs. Ag/AgCl) in 0.5 M NaSO solution and a significant increase in photocatalytic activity compared to SnS nanosheets. AgS (8 wt%)/SnS composite shows the highest activity (0.0440 mg/min) in the degradation of MO and good stability. The reactive species trapping experiments confirmed hole (h) and hydroxyl radical (OH) are active groups and play key roles in the photocatalytic degradation reaction. The highly effective photoelectrochemical and phocatalytic activities of AgS/SnS heterojunctions are attributed to the efficient separation of photogenerated hole-electron pairs. This work may provide a novel concept for the rational design of high performance SnS-based photocatalysts.