摘要：

通过水热法成功制备了Cu/Bi₂O₂S（Cu/BOS）光催化剂，采用扫描电子显微镜（SEM）、X射线衍射光谱（XRD）、紫外-可见漫反射光谱（UV-vis DRS）、光致发光光谱（PL）、电化学阻抗谱（EIS）及光电流响应等手段对催化剂进行了全面分析，考察了不同Cu掺杂量、催化剂投加量及H₂O₂浓度等对Cu/BOS+H₂O₂体系光催化降解结晶紫（CV）性能的影响，并探讨了该体系降解CV的作用机理。结果表明，Cu掺杂显著提升了BOS的光吸收能力并有效促进了光生载流子的分离。当Cu以1%的物质的量比掺杂于BOS（Cu/BOS-1）中，在50 mL 10 mg/L CV溶液中投加20 mg Cu/BOS-1和10 mmol/L H₂O₂条件下，光照90 min后CV降解率达94.99%。活性物种捕获实验和电子自旋共振（EPR）表明，在Cu/BOS+H₂O₂体系光催化降解CV过程中，·OH和O₂ ^·-是主要活性物种，且·OH发挥了主要作用。H₂O₂与光生e^-反应生成大量·OH，Cu/BOS也会与H₂O₂发生类Fenton反应，Cu（Ⅰ）/Cu（Ⅱ）的价态循环促进了·OH的持续生成。此外，Cu/BOS催化剂表现出优异的稳定性，在4次循环使用后仍保持94%以上的CV降解率，且结构未发生明显变化。

关键词: 硫氧化铋, 类Fenton, 光催化降解, 结晶紫

Abstract:

Cu/Bi₂O₂S (Cu/BOS) photocatalysts were successfully synthesized via a hydrothermal method and comprehensively characterized by scanning electron microscopy(SEM), X-ray diffraction(XRD), UV-vis diffuse reflectance spectroscopy(DRS), photoluminescence spectroscopy(PL), electrochemical impedance spectroscopy(EIS), and photocurrent response measurements. The effects of Cu doping amount, catalyst dosage, and H₂O₂ concentration on photocatalytic degradation of crystal violet(CV) in the Cu/BOS+H₂O₂ system were systematically investigated, and the degradation mechanism was elucidated. The results demonstrated that Cu doping significantly enhanced the light absorption capacity of BOS and effectively promoted the separation of photogenerated charge carriers. When Cu was doped into BOS (Cu/BOS-1) at a concentration of 1%, under the conditions of adding 20 mg Cu/BOS-1 and 10 mmol/L H₂O₂ to 50 mL of 10 mg/L CV solution, the CV degradation rate reached 94.99% after 90 minutes of light irradiation. The active species trapping experiments and electron paramagnetic resonance(EPR) indicated that ·OH and O₂ ^·- were the main active species in the photocatalytic degradation of CV in Cu/BOS+H₂O₂ system, and ·OH played a major role. H₂O₂ reacted with electrons (e^-) generated by photo to generate substantial ·OH. Simultaneously, a Fenton-like reaction occurred between Cu/BOS and H₂O₂, where the Cu(Ⅰ)/Cu(Ⅱ) redox cycle facilitated the sustained generation of ·OH. Furthermore, the Cu/BOS catalyst exhibited excellent stability, maintaining over 94% CV degradation rate after four consecutive reuse cycles without significant structural changes.

Key words: Bi₂O₂S, Fenton-like, photocatalytic degradation, crystal violet

中图分类号: 

• X703.1