La-doped Bi2O3 were prepared via a simple sol–gel method following a facile low temperature calcination process, and citric acid as an organic complexing agent. La3+ doping could not only create oxygen vacanices (OVs) on the surface of Bi2O3, but also as the efficient scavenger to capture photogenerated electrons. The novel x% La–Bi2O3 photocatalysts exhibited oxidation capacities for degrading azo dye methyl orange (MO) and colorless pollutant phenol, and 2% La–Bi2O3 sample showed the highest photocatalytic activity. The enhanced photocatalytic activity in MO and phenol photo-degradation were attributed to the strong synergistic effects of La3+-doping and oxygen vacancies (OVs), which La3+ ions capture, transfer, and release the photo-generated electrons for conversion from O2 to ·O2-\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ ^{ \cdot } O_{2}^{ - } $$\end{document} to prevent the hot e− of CB to jump into the level of OVs, thereby increase separation efficiencies of photo-generated electrons and holes. The present study may present a new perspective for the utilization of rare earth ion doping to improve the performance of other photocatalytic materials.

中文翻译：

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制备具有氧空位的 La 掺杂 Bi2O3 纳米颗粒以提高光催化活性

La 掺杂的 Bi2O3 是通过简单的溶胶-凝胶法通过简单的低温煅烧工艺和柠檬酸作为有机络合剂制备的。La3+ 掺杂不仅可以在 Bi2O3 表面产生氧空位 (OVs)，还可以作为捕获光生电子的有效清除剂。新型 x% La-Bi2O3 光催化剂表现出降解偶氮染料甲基橙 (MO) 和无色污染物苯酚的氧化能力，2% La-Bi2O3 样品显示出最高的光催化活性。MO 和苯酚光降解中增强的光催化活性归因于 La3+ 掺杂和氧空位 (OVs) 的强烈协同作用，其中 La3+ 离子捕获、转移、并释放光生电子以从 O2 转换为·O2-\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage {mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ ^{ \cdot } O_{2}^{ - } $$\end{document} 防止热e - CB 跳到 OVs 的水平，从而提高光生电子和空穴的分离效率。本研究可能为利用稀土离子掺杂改善其他光催化材料的性能提供新的视角。