Application of Z-scheme Bi2O3-Ag3PO4 Composite Photocatalyst in Degradation of Tetracycline and Methyl Orange

A new type of visible light Z-scheme Bi2O3-Ag3PO4 composite photocatalyst was created in this work using a simple in-situ precipitation process. On this basis, the morphology, optical properties and electrochemical performance of the photocatalyst were studied by N-2 adsorption-desorption analysis and XRD, FT-IR, XPS, SEM, TEM, UV-vis DRS, PL, EIS, and other characterization methods. To further explore the photocatalytic performance of the composites, visible light degradation experiments were carried out on the antibiotic TC and the organic dyes MB and MO. The results show that the 0.025BA composite material exhibits higher photocatalytic performance than other comparative samples. In addition, the 0.025BA composite after five cycles of experiments also has a satisfactory photodegradation rate. The active species capture experiment and ESR showed that the active species h(+), O-center dot(2-) are the main factors affecting the photocatalytic degradation, and (OH)-O-center dot played a minor role. The intermediates and possible decomposition pathways of TC were illustrated through LC-MS technology. Finally, the possible photocatalytic reaction mechanism was speculated. On the whole, the high photocatalytic activity of the 0.025BA composite is perhaps the result of the formation of its Z-scheme heterojunction, which enables fast transfer and high separation of photogenerated carriers at the heterojunction interface, and also accelerates the rate of redox reactions on electron-hole pairs.