In situ synthesis of AgI/SnS2 heterojunction photocatalysts with superior photocatalytic activity

In present study, novel visible-light-driven photocatalyst AgI/SnS2 heterojunctions were prepared with hydrothermal-precipitation method. The resulting AgI/SnS2 heterojunctions exhibited superior and stable visible photocatalytic activity on Rhodamine B (RhB) removal. The optimal heterojunction with 4:1 mass ratio of AgI: SnS2 exhibited the highest rate constant of 0.064 min(-1) for removal of RhB, which was about 2.1 and 3.4 times as much as pure AgI and SnS2, respectively. In addition, the study by photoluminescence spectroscopy (PL) indicated that the improvement of the photocatalytic efficiency could be mainly owing to the truth that the photogenerated carriers were separated and transferred effectively, resulted from the appropriate band gap match of AgI and SnS2. In addition, it was found that center dot O-2(-) radicals and h(+) were the main oxidative species responsible for removal of RhB. These features demonstrate that AgI/SnS2 heterojunction has great application potentials for pollutants removal from wastewater.