BiVO4/WO3-x S型异质结通过增强内建电场提升光热催化活性

引用本文: 龙子洋, 李全政, 张成亮, 史海峰. BiVO₄/WO_3-x S型异质结通过增强内建电场提升光热催化活性[J]. 物理化学学报, 2025, 41(10): 100122. doi: 10.1016/j.actphy.2025.100122 shu

Citation: Ziyang Long, Quanzheng Li, Chengliang Zhang, Haifeng Shi. BiVO₄/WO_3-x S-scheme heterojunctions with amplified internal electric field for boosting photothermal-catalytic activity[J]. Acta Physico-Chimica Sinica, 2025, 41(10): 100122. doi: 10.1016/j.actphy.2025.100122 shu

BiVO₄/WO_3-x S型异质结通过增强内建电场提升光热催化活性

1.
江南大学理学院, 江苏无锡 214122
2.
杭州电子科技大学微电子研究所, 浙江杭州 310018
3.
南京大学固体微结构物理国家重点实验室, 江苏南京 210093

通讯作者: 史海峰, hfshi@jiangnan.edu.cn

基金项目:
国家自然科学基金 52271175

南京大学固体微结构国家重点实验室开放课题 M34047

江苏省青蓝工程项目

摘要: 增强S型异质结光催化剂中的内建电场(IEF)的强度对于解决环境问题具有独特的优势。于此，本文通过水热法成功制备了BiVO₄/WO_3-x S型异质结光热催化材料，并通过在可见光照射下同时降解四环素(TC)和六价铬(Cr(Ⅵ))系统地研究了BiVO₄/WO_3-x的催化活性。实验结果表明，在单一污染物的降解中，BiVO₄/WO_3-x相较于两种单质材料表现出明显增强的催化活性：在可见光照射60 min后，对TC和Cr(Ⅵ)的降解效率分别达到了78.5%和85.3%。同时，复合材料在TC和Cr(Ⅵ)的混合体系中的协同光催化活性得到了提高，Cr(Ⅵ)和TC的去除能力分别提高了1.29倍和1.32倍。红外热成像仪的分析结果表明了WO_3-x的光热效应可以提高反应体系的温度。DFT计算的结果表明，氧空位的引入增强了两种材料间的费米能级差，从而促进了光生载流子的分离。利用绿豆种子的生长实验和液相色谱-质谱仪(LC-MS)的检测结果对TC的降解路径和中间产物的毒性进行了详细的分析。本研究为设计和开发用于协同去除含有Cr(Ⅵ)和TC的水体的S型光热催化材料提供了新的思路。

关键词:

English

BiVO₄/WO_3-x S-scheme heterojunctions with amplified internal electric field for boosting photothermal-catalytic activity

1.
School of Science, Jiangnan University, Wuxi 214122, Jiangsu Province, China
2.
Microelectronics Research Institute, Hangzhou Dianzi University, Hangzhou 310018, Zhejiang Province, China
3.
National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, Jiangsu Province, China

Corresponding author: Haifeng Shi, Email: hfshi@jiangnan.edu.cn

Received Date: 13 May 2025
Accepted Date: 15 June 2025
Revised Date: 13 June 2025
Available Online: 15 October 2025
Fund Project:
the National Natural Science Foundation of China

National Laboratory of Solid State Microstructures, Nanjing University

the Qing Lan Project of Jiangsu Province

Abstract: Modulating the internal electric field (IEF) remains a critical challenge for S-scheme heterojunction photocatalysts. The BiVO₄/WO_3-x S-scheme heterojunctions were successfully prepared to purify the wastewater environment where tetracycline (TC) and Cr(Ⅵ) coexist under visible light illumination. The BiVO₄/WO_3-x with 10% (wt) WO_3-x (BVO/WO_3-x-10) demonstrated superior photocatalytic efficiency, which could degrade 78.5% of TC and reduce 85.3% of Cr(Ⅵ) in 60 min. The photocatalytic activity of BVO/WO_3-x-10 displayed enhanced removal efficiency in the mixed system. The removal ability of TC and Cr(Ⅵ) was increased by 1.29 and 1.32 times, respectively. Based on infrared thermography (IR) thermography measurements, the elevated reaction system temperatures were ascribed to the photothermal effect of WO_3-x. Oxygen vacancies (OVs) could amplify the energy band difference between WO_3-x and BiVO₄, which strengthens the IEF and accelerates the separation of carriers. A detailed degradation pathway and intermediate toxicity were carried out using the mung bean experiment and the results of the Liquid Chromatograph Mass Spectrometer (LC-MS). In general, this work provided new insights for regulating IEF to enhance the degradation efficiency in mixed wastewater and the carriers separation in the S-scheme heterojunction of the photothermal-catalytic system.

Key words:

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1.
沈阳化工大学材料科学与工程学院沈阳 110142

BiVO₄/WO_3-x S型异质结通过增强内建电场提升光热催化活性

通讯作者: 史海峰, hfshi@jiangnan.edu.cn

English

BiVO₄/WO_3-x S-scheme heterojunctions with amplified internal electric field for boosting photothermal-catalytic activity

Corresponding author: Haifeng Shi, Email: hfshi@jiangnan.edu.cn

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