催化学报 ›› 2022, Vol. 43 ›› Issue (2): 472-484.DOI: 10.1016/S1872-2067(21)63876-7

• 论文 • 上一篇    下一篇

溶剂热合成可调控氧空位的Bi2MoO6纳米晶及其光催化氧化制喹啉和抗生素降解

刘珍a,, 田坚b,, 余长林a,*(), 樊启哲a, 刘兴强c,#()   

  1. a广东石油化工学院化学工程学院, 环境科学与工程学院, 岭南现代农业科学与技术广东省实验室茂名分中心, 广东茂名 525000
    b哈尔滨工业大学(深圳)理学院, 城市水资源与水环境国家重点实验室, 广东深圳 518055
    c厦门大学嘉庚学院环境科学与工程学院, 河口生态安全与环境健康福建省高校重点实验室, 福建漳州 363105
  • 收稿日期:2021-05-01 接受日期:2021-05-01 出版日期:2022-02-18 发布日期:2021-07-02
  • 通讯作者: 刘珍,田坚,余长林,刘兴强
  • 基金资助:
    广东省高等学校珠江学者特聘教授资助计划(2019);广东省基础与应用基础研究基金(2019A1515011249);广东省基础与应用基础研究基金(2021A1515010305);广东省基础与应用基础研究基金(2020A1515110736);广东省教育厅自然科学重点研究项目(2019KZDXM010);广东省重点研发计划项目(2019B110206002);茂名市科技计划项目(2020KZX035);茂名市科技计划项目(2020KJZX034)

Solvothermal fabrication of Bi2MoO6 nanocrystals with tunable oxygen vacancies and excellent photocatalytic oxidation performance in quinoline production and antibiotics degradation

Zhen Liua,, Jian Tianb,, Changlin Yua,*(), Qizhe Fana, Xingqiang Liuc,#()   

  1. aSchool of Chemical Engineering, School of Environmental Science and Engineering, Maoming Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong University of Petrochemical Technology, Maoming 525000, Guangdong, China
    bSchool of Science, State Key Lab of Urban Water Resource and Environment, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, Guangdong, China
    cSchool of Environmental Science and Engineering, Key Laboratory of Estuarine Ecological Security and Environmental Health, Xiamen University Tan Kah Kee College, Zhangzhou 363105, Fujian, China
  • Received:2021-05-01 Accepted:2021-05-01 Online:2022-02-18 Published:2021-07-02
  • Contact: Zhen Liu, Jian Tian, Changlin Yu, Xingqiang Liu
  • Supported by:
    This work was supported by the Guangdong Province Universities and Colleges Pearl River Scholar Funded Scheme(2019);Guangdong Basic and Applied Basic Research Foundation(2019A1515011249);Guangdong Basic and Applied Basic Research Foundation(2021A1515010305);Guangdong Basic and Applied Basic Research Foundation(2020A1515110736);Key Research Project of Natural Science of Guangdong Provincial Department of Education(2019KZDXM010);Guangdong Provincial Key R&D Programme(2019B110206002);Maoming Science and Technology Special Plan Project(2020KZX035);Maoming Science and Technology Special Plan Project(2020KJZX034)

摘要:

近年来, 半导体光催化在环境净化和有机合成领域的研究引起了广泛的重视. 其中, 在有机合成领域中, 光催化技术已经应用在醇类、环己烷以及芳香族化合物的选择性氧化研究. 而另一类具有特殊结构的有机物——N-杂环芳烃, 在药物化学和材料科学中具有重要意义. 而传统用于合成N-杂化芳烃的脱氢催化氧化反应通常需要高温高压的苛刻环境, 传统方法通常还需要使用贵金属催化剂, 这也增加了N-杂化芳烃的合成成本; 另外, 如果合成是均相催化过程, 则催化剂难以实现回收利用. 因此, 开发室温常压条件下的非贵金属多相光催化技术具有巨大的应用前景.
本文以能够被可见光驱动的钼酸铋半导体为催化剂, 利用氧缺陷策略来提升钼酸铋的光催化氧化性能. 不同于传统氧缺陷制备方法(氢气还原热处理、离子掺杂等), 本文采用一种低成本的乙二醛辅助溶剂热的方法合成具有可调控的含氧空位Bi2MoO6催化剂(OVBMO). 通过X射线粉末衍射(XRD)、扫描电镜、透射电镜、紫外可见漫反射吸收光谱、氮气物理吸附脱附、X射线光电子能谱(XPS)、电子自旋共振光谱、光致发光光谱及电化学测试等技术对制备的OVBMO材料进行了物理化学性质及能带研究. XPS, XRD, Raman和FT-IR结果表明, 氧空位存在于[Bi2O2] 2+和MoO6八面体的层间. 紫外可见漫反射结果表明, 随着氧空位的引入, Bi2MoO6的光吸收范围扩大, 带隙变窄. 结合莫特肖特基和VBXPS分析获得OVBMO的能带位置, 发现氧空位的存在不仅会导致禁带中出现缺陷带能级, 还会导致价带顶位置上移, 促进光生空穴的迁移. PL和电化学结果表明, 氧空位的存在使得载流子浓度、载流子的分离能力与界面电荷迁移能力都有较大提升, 这是因为氧空位引入的缺陷能级可以浅势捕获电子, 抑制光催化剂中的电子与空穴的复合, 改变化学反应的速率. 同时, 氧空位有助于捕获分子氧, 分子氧与捕获的光生电子发生反应, 产生更多的超氧自由基(•O2)和空穴(h +), 从而极大地提升光催化剂的氧化性能. 因此, OVBMO在1,2,3,4-四氢喹啉脱氢氧化产生喹啉及系列抗生素(环丙沙星、四环素、盐酸土霉素)的降解反应中, 表现出较好的光催化氧化性能. 结合多种表征分析, 本文还进一步阐明了OVBMO催化剂将1,2,3,4-四氢喹啉脱氢氧化为喹啉的自由基参与的多相催化反应机理.

关键词: Bi2MoO6纳米晶体, 氧空位, 光催化氧化性能, 喹啉生产, 抗生素降解

Abstract:

Novel Bi2MoO6 nanocrystals with tunable oxygen vacancies have been developed via a facile low-cost approach with the assistance of a glyoxal reductant under solvothermal conditions. With the introduction of oxygen vacancies, the optical absorption of Bi2MoO6 is extended and its bandgap narrowed. Oxygen vacancies not only lead to the appearance of a defect band level in the forbidden band but can also result in a minor up-shift of the valence band maximum, promoting the mobility of photogenerated holes. Moreover, oxygen vacancies can act as electron acceptors, temporarily capturing electrons excited by light and reducing the recombination of electrons and holes. At the same time, oxygen vacancies help to capture oxygen, which reacts with the captured photogenerated electrons to generate more superoxide radicals (•O2 -) to participate in the reaction, thereby significantly promoting the redox performance of the photocatalyst. From Bi2MoO6 containing these oxygen vacancies (OVBMO), excellent photocatalytic performance has been obtained for the oxidation of 1,2,3,4-tetrahydroquinoline to produce quinoline and cause antibiotic degradation. The reaction mechanism of the oxidation of 1,2,3,4-tetrahydroquinoline to quinoline over the OVBMO materials is elucidated in terms of heterogeneous Catal. via a radical pathway.

Key words: Bi2MoO6 nanocrystals, Oxygen vacancies, Photocatalytic oxidation performance, Quinoline production, Antibiotics degradation