Preparation of porous g-C3N4/Ag/Cu2O: a new composite with enhanced visible-light photocatalytic activity

摘要

From previous reports, graphitic carbon nitride (g-C3N4) can be used as a photocatalyst, although the lowefficiency of solar energy utilization, small specific surface area and high recombination rate of photogenerated electron-hole pairs limit its practical application. For the purpose of increasing photocatalytic activity, especially under irradiation of visible light, we successfully synthesized a new composite, namely porous g-C3N4/Ag/Cu2O, through chemical adsorption of Ag-doped Cu2O on porous g-C3N4, which has not been investigated carefully worldwide. The composition, morphology and optical properties of the composite were investigated through methods including X-ray diffraction, energy-dispersive X-ray, Fourier transform infrared, UV-visible and photoluminescence spectroscopies and transmission electron microscopy. Using rhodamine B as organic pollutant to be degraded under the irradiation of visible light, differentmass ratios of Ag/Cu2O doped on porous g-C3N4 led to enhanced photocatalytic performance of the composite compared to pure porous g-C3N4. When the mass ratio of Ag/Cu2O is 15%, porous g-C3N4/Ag/Cu2O exhibits a degradation rate 2.015 times higher than that of pure porous g-C3N4. The reasons for this phenomenon may be attributed to the increased utilization efficiency of visible light, high-speed separation of photogenerated electron-hole pairs, accelerated interfacial transfer process of electrons and increased surface area of the composite. Copyright (C) 2016 John Wiley & Sons, Ltd.