【摘要】 异质结构建可有效促进电子-空穴对分离和转移，延长载流子的寿命，提升光催化剂性能。以L-半胱氨酸作为模板剂，采用原位水热法合成了类羽毛状Bi₂S₃/Bi₂O₃（BSO）异质结，考察了模板剂用量和溶液pH值对光催化还原六价铬（Cr（VI））性能的影响，并通过活性自由基捕获实验和光电化学表征探讨了其光催化机制。结果表明：在Bi原子和半胱氨酸的摩尔比为1∶1及溶液pH=2条件下，经过4 h的可见光照射，Cr（VI）的还原率达98.69%,较纯Bi₂O₃和Bi₂S₃分别提升了54.55倍、32.04倍；高光催化活性归因于高比表面积、有效的可见光响应及Bi₂S₃/Bi₂O₃异质结的形成，界面内建电场生成可为光生电子和空穴有效分离提供途径。更多还原

【Abstract】 Heterojunction building can effectively promote the separation and transfer of electron-hole pair, prolong the lifetime of charge carriers, and enhance the performance of photocatalysts. In this paper, feather-like Bi₂S₃/Bi₂O₃（BSO） heterojunctions were synthesized by in situ hydrothermal method using L-cysteine as a template agent. The effects of template agent dosage and solution pH on the performance of photocatalytic reduction of hexavalent chromium（Cr（VI）） were investigated, and the photocatalytic mechanism was explored by reactive radicals trapping experiments and photoelectrochemical characterization. The results show that the reduction rate of Cr（VI） reaches 98.69% after 4 h of visible light irradiation at a molar ratio of Bi atoms to cysteine of 1∶1 and a solution pH of 2, which is 54.55 and 32.04 times higher than that of pure Bi₂O₃ and Bi₂S₃, respectively. The high photocatalytic activity is attributed to the high specific surface area, effective visible light response and the formation of Bi₂S₃/Bi₂O₃ heterojunction, and the built-in electric field generation at the interface can provide a pathway for the effective separation of photogenerated electrons and holes.更多还原