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It is a practical way to raise the efficiency of photocatalysis by using oxygen vacancy defect modified materials. In this experiment, a Z‐scheme BOA composite photocatalyst with defect structure was prepared by hydrothermal in situ precipitation method. The optimal ratio of 1.5 BOA showed excellent photocatalytic degradation performance for MO, TC and CIP under visible light irradiation, and maintained good structural stability and circulation rate after five cycles. The increased photocatalytic activity of the composite can be explained to the heterojunction interface's synergistic effects and the quicker electron hole transit rate caused by the surface oxygen vacancy defect. XPS and EPR confirmed the existence of anoxic structure in the composite, PL and photocurrent confirmed the high electron hole transfer rate. The active species that contributed to the degradation process were validated by the active species capture experiment and ESR. LC–MS speculated the possible degradation path of CIP. Finally speculated the reaction mechanism of Z‐scheme BOA composite photocatalyst. Using the anoxic structure of BiO2−X to form a Z‐scheme heterostructure with Ag3PO4, the oxygen vacancy as the electron capture center and active site is conducive to improving the photogenerated electron transfer rate, thereby improving the structural stability and photocatalytic performance of the complex. [ABSTRACT FROM AUTHOR]

An excellent ternary Z-scheme photocatalytic heterojunction of g-C3N4 nanosheet/WO3/graphene oxide (CWG) was prepared by in-situ growth of WO3 during thermal exfoliation bulk g-C3N4 to g-C3N4 nanosheet, followed by electrostatic self-assembly of graphene oxide (GO) and g-C3N4 nanosheet in the HNO3 solution. The photocatalytic performance was evaluated by the degradation of rhodamine B (RhB) under visible light irradiation. The CWG heterojunction exhibited outstanding photocatalytic efficiency for RhB degradation, which was about 4.6 and 23 times that of CN and WO3, indicating the introduction of GO and WO3 improved the capability of the photocatalysis due to an efficient charge separation and transfer between g-C3N4 nanosheets and WO3. In addition, the possible for the enhancing photocatalytic mechanism was revealed based on the active species trapping and ESR analysis. [ABSTRACT FROM AUTHOR]

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 N2 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+, ⋅O2− are the main factors affecting the photocatalytic degradation, and ⋅OH 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. [ABSTRACT FROM AUTHOR]