Phase purification of Cu–S system towards Cu1.8S and its catalytic properties for a clock reaction†
Abstract
Controlling the composition and crystal phase is an important issue to tune material physical/chemical properties. Herein, it was found that triphenyl phosphine (TPP) can be used as a phase transfer agent to transform CuS, Cu39S28 phases into pure low-sulfur Cu1.8S phase. When mixed phase copper sulfides were reacted with triphenyl phosphine under suitable temperature, sulfur was extracted to produce the low-sulfur Cu1.8S phase. It was also demonstrated that the Cu–S product can effectively catalyze a clock reaction between methylene blue and hydrazine in aqueous medium. In addition, the photothermal conversion properties of the Cu–S based products were studied. The results show that the purified Cu1.8S materials show enhanced or similar properties than the original mixed-phase Cu–S products.