Z-scheme and multipathway photoelectron migration properties of a bayberry-like structure of BiOBr/AgBr/LaPO4 nanocomposites: Improvement of photocatalytic performance using simulated sunlight

In this paper, bayberry-like BiOBr/AgBr/LaPO4 nanocomposites were synthesized by microwave-assisted hydrothermal treatment. The composition, structure, and morphology of BiOBr/AgBr/LaPO4 nanocomposites were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-visible diffuse reflectance (UV-vis/DRS), high-power transmission electron microscopy (HR-TEM), scanning electron microscopy (SEM), and N-2 adsorption-desorption measurements. The results show that the light absorption capacity of BiOBr/AgBr/LaPO4 is clearly enhanced and that a bayberry-like structure is more likely to produce diffraction and reflection of light on the surfaces of composites. AgBr in the composite is capable of reducing to Ag-0 after light irradiation. Ag-0, acting as a charge-transfer mediator, can be the medium, thus forming a Z-scheme structure. At the same time, the surface plasmon resonance (SPR) effect of Ag-0 exhibits higher activity in the simulated sunlight photocatalysis process in BiOBr/AgBr/LaPO4. The photoelectrochemical methods further indicate that BiOBr/AgBr/LaPO4 possesses the best electron-hole pair separation ability. Furthermore, two different interface electron transfer modes and multipathway photoelectron migration in the composite are determined. (C) 2019 Elsevier B.V. All rights reserved.