微波水热/稀乙酸溶剂热法制备多形貌BiOBr及其光催化机制

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中图分类号：TQ426.6 文献标志码：A DOI： 10.3969/j.issn.1003-9015.2025.00.059

文章编号：1003-9015（2026）01-0133-13

Abstract：To address the issues associated with conventional hydrothermal/solvothermal methods for synthesizing multimorphic BiOBr，such as long heating times，high temperatures，and the necessity toad additional modifiers or templating agents. In this work，a microwave-assisted hydro/solvothermal method was first employed to rapidly synthesize four distinct BiOBr morphologies （spherical （BiOBrU1） ， flower-like （BiOBrU2） ），thick-sheet （BiOBrAl） ， and thin-sheet （BiOBrA2） ） within 2 hours，using only readily available ultrapure water and dilute acetic acid as solvents and modulatingonlythe reaction temperature.Optical characterization demonstrated visible-light absorption capability for all BiOBr photocatalysts， with absorption edges around 440nm ： BiOBrU1 ， BiOBrU2 exhibited stronger absorption in the UV-Vis region. The photocatalytic degradation performance was evaluated using tetracycline （TC） and ciprofloxacin （CIP） antibiotics. Under visible light irradiation for 120 minutes，both BiOBrU1 （20 and BiOBrU2 demonstrated favorable catalytic degradation activity. Notably， BiOBrU1 achieved a degradation efficiency of approximately 76% for a 20mg⋅L-1 TC solution.Besides， the TC degradation still reached 51% after under through three cycling experiments.Furthermore，the band structures and work functions of the four BiOBr samples were elucidated through combined characterization analysis and DFTcalculations.The valence band （VB） position of the sheet-like BiOBr was determined to be sufficiently positive to generate strongly oxidizing photogenerated holes （h+） ，reacting with -OH to produce primarily ·OH as the oxidizing active species. BiOBrU1 microspheres possessed the highest oxidation and reduction potentials for their VB and conduction band （CB） positions，enabling the generation of both ⋅O2- via highly reductive photogenerated electrons and ·OH via photogenerated ℏ+ .This study provides a theoretical reference and technical support for the design and synthesis of BiOBr photocatalysts.

Key words： BiOBr； morphology control； photocatalytic degradation； microwave heating； densityfunctional theory

1前言

BiOBr是一种典型的半导体光催化材料，其独特的层状结构有利于光生电子-空穴对的分离。（剩余18287字）