An S-Scheme MIL-101(Fe)-on-BiOCl Heterostructure with Oxygen Vacancies for Boosting Photocatalytic Removal of Cr(VI)

作者：Chunchun Wang, Changjun You, Ke Rong, Chuqi Shen, Fang Yang, Shijie Li · 发表于：Acta Physico-Chimica Sinica · 年份：2023 · DOI：10.3866/pku.whxb202307045 · 被引用次数：242 · 研究领域：Advanced Photocatalysis Techniques、Catalytic Processes in Materials Science、Gas Sensing Nanomaterials and Sensors

Hexavalent chromium (Cr(VI)) may be a hazardous and nonbiodegradable waste matter which will cause substantial environmental damage. Fabricating powerful photosystems to achieve efficacious elimination of Cr(VI) holds eminent promise in solving environmental issues. Thanks to their outstanding photo/electrical properties, large surface area , and customizable structure, metal-organic framework (MOF) catalysts have attracted widespread attention within the field of pollutant degradation and reduction. Nevertheless, due to the recombination of photo-generated charge carriers, pristine semiconductor MOFs’ photocatalytic performance is inadequate. To overcome this challenge, one of the most typical and effective strategies is to create heterojunctions by combining MOFs with another semiconductor. Among these strategies, the innovative step-scheme (S-scheme) heterojunction has gained increasing prominence. Unlike traditional type II and Z-scheme heterojunctions , the built-in electric field at the S-scheme heterojunction boundary enhances spatial charge separation and boosts redox capacity, thereby improving photocatalytic performance. In this study, a creative MOF-based S-scheme architecture with oxygen vacancies (OV) was built via in situ growth of MIL-101(Fe) crystals on the surface of OV-rich BiOCl microspheres . The optimized MIL-101(Fe)/BiOCl heterojunction exhibited exceptional photocatalytic performance in photo-reducing high concentrations of Cr(VI) and 88.5% of Cr(VI) so...