大规模合成具有氧空位的多孔Bi2O3用于有效降解亚甲基蓝

光催化降解有机污染物由于其具有低能耗和绿色环保的特点，已经成为研究的热点. 氧化铋纳米晶体的带隙在2.0∽2.8 eV之间，利用它催化可见光降解有机污染物具有较高的活性，从而引起了越来越多的关注. 尽管近年来已经开发了几种制备Bi₂O₃基半导体材料的方法，但是仍然难以用简单的方法大规模地制备高活性的Bi₂O₃催化剂. 因此，开发简单可行的大规模制备Bi₂O₃纳米晶体的方法对于工业废水处理的潜在应用具有重要意义. 本文通过蚀刻商用BiSn粉末，然后进行热处理，成功地大规模制备了多孔Bi₂O₃. 获得的多孔Bi₂O₃在亚甲基蓝(MB)的光催化降解中表现出优异的活性和稳定性. 对该机理的进一步研究表明，多孔Bi₂O₃合适的能带结构允许生成活性氧物种，例如O₂^-·和·OH，可有效降解MB.

Large-Scale Synthesis of Porous Bi2O3 with Oxygen Vacancies for Efficient Photodegradation of Methylene Blue

Photocatalytic degradation of organic pollutants has become a hot research topic because of its low energy consumption and environmental-friendly characteristics. Bismuth oxide (Bi₂O₃) nanocrystals with a bandgap ranging from 2.0 eV to 2.8 eV have attracted increasing attention due to high activity of photodegradation of organic pollutants by utilizing visible light. Though several methods have been developed to prepare Bi₂O₃-based semiconductor materials over recent years, it is still difficult to prepare highly active Bi₂O₃ catalysts in large scale with a simple method. Therefore, developing simple and feasible methods for the preparation of Bi2O3 nanocrystals in large scale is important for the potential applications in industrial wastewater treatment. In this work, we successfully prepared porous Bi₂O₃ in large scale via etching commercial BiSn powders, followed by thermal treatment with air. The acquired porous Bi₂O₃ exhibited excellent activity and stability in photocatalytic degradation of methylene blue. Further investigation of the mechanism witnessed that the suitable band structure of porous Bi₂O₃ allowed the generation of reactive oxygen species, such as O₂^-· and ·OH, which effectively degraded MB.