科研进展

中文标题：表面缺陷可调的Bi₄Ti₃O₁₂纳米片用于光催化降解抗生素左氧氟沙星

英文标题：Surface defects engineered Bi₄Ti₃O₁₂ nanosheets for photocatalytic degradation of antibiotic levofloxacin

期刊名称及期号、页码：Applied Catalysis A: General, 2022，640，118675.

作者姓名（中文）：位顺航，陈禹行，吴萍如，刘新根，任俊，姚博，徐海涛，窦卫东，汪亚威，吴荣，方泽波^*，梁奇峰^*

作者姓名（英文）：Shunhang Wei, Yuxing Chen, Pingru Wu, Xingen Liu, Jun Ren, Bo Yao, Haitao Xu, Weidong Dou, Yawei Wang, Rong Wu, Zebo Fang^*, Qifeng Liang^*

摘要（英文）：Surface defects have a significant effect on the photocatalytic reaction of Bi₄Ti₃O₁₂, but the mechanism is unclear. In addition, when surface defects and highly exposed facets exist at the same time, which factor plays the main role in photocatalytic activity is also controversial. Herein, it is found that Bi₄Ti₃O₁₂ with adjustable concentrations of surface defects and percentage of exposed {001} facets can be prepared by using titania of different crystal types and sizes as raw materials, which is extremely beneficial for exploring the above problems. The photocatalytic activity of Bi₄Ti₃O₁₂ nanosheets with surface defects and exposed {001} facets was the same as that of Bi₄Ti₃O₁₂ nanosheets with surface defects alone (about 72.5% of photodegradation levofloxacin under 10 min of simulated sunlight irradiation). Based on the experimental results and density functional theory calculations, the influence mechanism of surface defects was deeply studied. The surface defects resulting from partial exfoliation of the external (Bi₂O₂)²⁺ layers changed band structure of Bi₄Ti₃O₁₂. More importantly, surface defects with high concentration became hole trapping sites, which was conducive to the faster participation of holes in the photocatalytic oxidation process.

摘要（中文）：表面缺陷对Bi₄Ti₃O₁₂光催化反应有显著影响，但机理尚不清楚。此外，当表面缺陷和高暴露面同时存在时，哪一个因素对光催化活性起主要作用也存在争议。本文发现，以不同晶型和尺寸的二氧化钛为原料，可以制备出表面缺陷浓度可调、{001}暴露面百分比可调的Bi₄Ti₃O₁₂，这对探索上述问题极为有利。同时具有表面缺陷和{001}暴露面的Bi₄Ti₃O₁₂纳米片的光催化活性与只具有表面缺陷的Bi₄Ti₃O₁₂纳米片的光催化活性相同(在模拟太阳光照射10 min，光降解左氧氟沙星约72.5%)。基于实验结果和密度泛函理论计算，对表面缺陷的影响机理进行了深入研究。外部(Bi₂O₂)²⁺层部分脱落导致的表面缺陷改变了Bi₄Ti₃O₁₂的能带结构。更重要的是，高浓度的表面缺陷成为空穴捕获位点，有利于空穴更快地参与光催化氧化过程。

创新点：该工作发现以不同晶型和尺寸的二氧化钛为原料可以制备表面缺陷浓度可调、{001}暴露面百分比可调的Bi₄Ti₃O₁₂纳米片。通过对比发现，对于Bi₄Ti₃O₁₂纳米片，相较于高暴露面，外部(Bi₂O₂)²⁺层部分脱落导致的表面缺陷对其光催化活性起到更重要的作用。

全文链接：

https://www.sciencedirect.com/science/article/abs/pii/S0926860X22001983