Ion-exchange synthesis of Ag/Ag_2S/Ag_3CuS_2 ternary hollow microspheres with efficient visiblelight photocatalytic activity

摘要

Ternary Ag/Ag_2S/Ag_3CuS_2 hollow microspheres were synthesized via an in situ ion-exchange method using Cu_7S_4 hollow submicrospheres as the template. The as-obtained Ag/Ag_2S/Ag_3CuS_2 composite exhibited a well-defined uniform hollow microsphere morphology with an average diameter of about 1.3 μm. The photocatalytic property of the as-prepared Ag/Ag_2S/Ag_3CuS_2 hollow microsphere composite was investigated by the decomposition of methyl orange (MO) under visible light irradiation (λ > 420 nm). It was shown that the photocatalytic activity of the Ag/Ag_2S/Ag_3CuS_2 hollow microsphere was higher than those of Ag/Ag_2S, Cu_2O, Cu_7S_4 and P25 for the photodegradation of MO under visible light irradiation. Radical scavenger experiments demonstrated that superoxide radicals and holes were the main reactive species for MO degradation.