摘要

A novel 0D/2D Z-scheme AgI/Bi(24)O(31)Br(10)photocatalyst was prepared through the simple solvothermal and coprecipitation method, in which AgI nanoparticles were decorated on the surface of Bi(24)O(31)Br(10)nanosheets. The AgI/Bi(24)O(31)Br(10)composites exhibited improved photocatalytic activity for the degradation of rhodamine B (RhB) in comparison with pristine Bi(24)O(31)Br(10)and AgI under simulated sunlight irradiation. Specifically, AB-30 (mass fraction of AgI, 30%) composite exhibited remarkable photocatalytic activity of 97.6% towards RhB degradation under 120 min of simulated sunlight irradiation, and its RhB degradation rate constant (k) was approximately 20.7 and 2.9 times higher than that of pure Bi(24)O(31)Br(10)and AgI, respectively. The improvement of photocatalytic performance of as-prepared AgI/Bi(24)O(31)Br(10)heterojunction composites was ascribed to the synergistic effect of wide visible-light harvest capacity and the rapid transfer and separation efficiency of charge carriers. UV-vis diffuse reflectance spectra (DRS) analysis validated that the introduction of AgI could broaden the visible-light absorption of AgI/Bi(24)O(31)Br(10)composite. The results of electrochemical impedance (EIS), photocurrent response and photoluminescence spectra (PL) tests showed that AgI/Bi(24)O(31)Br(10)composite possessed the efficient separation and migration of photogenerated charge carriers. Trapping experiments of free radicals certified that center dot O(2)(-)was the main reactive species in the process of degradation. And a probable photocatalytic mechanism of Z-scheme heterojunction between Bi(24)O(31)Br(10)and AgI was proposed.