Synthesis of AgI/WS 2 hybrids as a novel photocatalyst with efficient degradation of rhodamine B

Abstract

Full-spectrum-responsive AgI/WS2 composites as an efficient photocatalyst have been synthesised by an in-situ growth of AgI on the surfaces of WS2 nanosheets. The photocatalytic activities of the samples were evaluated by degradation of rhodamine B dilute solution under visible light irradiation. Experimental results showed that the introduction of WS2 nanosheets could enhance light absorption, photocatalytic activity, and recyclability of the pure AgI in the region of visible and infrared light. Moreover, the degradation efficiency of the as-synthesised AgI/WS2 composites exhibited the trend of first increased and then decreased with increasing the amount of WS2 nanosheets. When the usage of WS2 nanosheets was 7 wt%, the as-prepared composites possessed the maximum of 91.2% in 30 min. Furthermore, after three cycles of degradation, it could still degrade 89.0% of rhodamine B, obviously higher than 11.4% of pure AgI. In addition, a possible degradation mechanism of the as-synthesised AgI/WS2 hybrids was provided.