Preparation of Z-scheme Ag/AgBr/BiOBr composite photocatalyst for effective removal of organic pollutants

A Z-scheme Ag/AgBr/BiOBr photocatalyst was synthesized via photoreduction-precipitation method and the samples were characterised by X-ray diffraction, X-ray electron spectroscopy, transmission electron microscopy, and photoluminescence spectroscopy. Experiments on photodegradation of methyl orange (MO), toluene and ethylbenzene under visible light revealed that Ag/AgBr/BiOBr nanocomposites can effectively remove organics pollutant. The degradation rate of MO could reach 90.5% within 2 h, which is approximately 39 times more efficient than the photocatalytic action of BiOBr. The improvement of Ag/AgBr/BiOBr photocatalytic performance can be attributed to its high electron-hole separation rate. A mechanism analysis indicated that Ag nanoparticle is a suitable intermediate of Z-scheme electron transfer pathway in the reaction system.