In-situ ion-exchange synthesis Ag2S modified SnS2 nanosheets toward highly photocurrent response and photocatalytic activity.

Abstract Heterojunction photocatalyst systems are deemed to be an excellent option to improve the photocatalytic behavior of a material. In this paper, Ag 2 S/SnS 2 heterojunction photocatalysts were prepared by a simple in-situ ion exchange method from SnS 2 nanosheets. The Ag 2 S/SnS 2 composite photoanode exhibits 13.99  μ A/cm 2 photocurrent density at 0.7 V ( vs . Ag/AgCl) in 0.5 M Na 2 SO 4 solution and a significant increase in photocatalytic activity compared to SnS 2 nanosheets. Ag 2 S (8 wt%)/SnS 2 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 Ag 2 S/SnS 2 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 2 -based photocatalysts.