催化学报 ›› 2024, Vol. 61: 247-258.DOI: 10.1016/S1872-2067(24)60047-1

• 论文 • 上一篇    下一篇

缺陷诱导电子-金属载体相互作用加速固液界面Fenton反应

毛海舫a, 刘洋a, 许振民a,*(), 卞振锋b,*()   

  1. a上海应用技术大学化学与环境工程学院, 上海 201418
    b上海师范大学资源化学教育部重点实验室, 稀土功能材料上海市重点实验室, 上海 200234
  • 收稿日期:2024-03-03 接受日期:2024-04-20 出版日期:2024-06-18 发布日期:2024-06-20
  • 通讯作者: * 电子信箱: bianzhenfeng@shnu.edu.cn (卞振锋), zhenminxufy@163.com (许振民).
  • 基金资助:
    国家重点研发计划项目(2020YFA0211004);国家自然科学基金项目(22376143);国家自然科学基金项目(22176128);国家自然科学基金项目(22236005);上海市教委创新计划项目(2023ZKZD50);上海市学术带头人计划项目(21XD1422800);上海市地方政府基金项目(22dz1205400);教育部重点实验室和国际资源化学联合实验室资助;上海东方学者计划;光化学与能源材料的111创新平台(D18020);上海市绿色能源化工工程技术研究中心(18DZ2254200);上海市科委上海市工程技术研究中心(20DZ2255600)

Defect-induced in situ electron-metal-support interactions on MOFs accelerating Fe(III) reduction for high-efficiency Fenton reactions

Haifang Maoa, Yang Liua, Zhenmin Xua,*(), Zhenfeng Bianb,*()   

  1. aSchool of Chemical and Environmental Engineering, Shanghai Institute of Technology, Shanghai 201418, China
    bMOE Key Laboratory of Resource Chemistry and Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University, Shanghai 200234, China
  • Received:2024-03-03 Accepted:2024-04-20 Online:2024-06-18 Published:2024-06-20
  • Contact: * E-mail: bianzhenfeng@shnu.edu.cn (Z. Bian); zhenminxufy@163.com (Z. Xu).
  • Supported by:
    National Key Research and Development Program of China(2020YFA0211004);National Natural Science Foundation of China(22376143);National Natural Science Foundation of China(22176128);National Natural Science Foundation of China(22236005);Innovation Program of Shanghai Municipal Education Commission(2023ZKZD50);Sponsored by Program of Shanghai Academic Research Leader(21XD1422800);Foundation from Shanghai Local Government(22dz1205400);Chinese Education Ministry Key Laboratory and International Joint Laboratory on Resource Chemistry;Shanghai Eastern Scholar Program;111 Innovation and Talent Recruitment Base on Photochemical and Energy Materials(D18020);Shanghai Engineering Research Center of Green Energy Chemical Engineering(18DZ2254200);Shanghai Frontiers Science Center of Biomimetic Catalysis and the Shanghai Engineering Technology Research Center of Shanghai Science and Technology Commission(20DZ2255600)

摘要:

水体污染物的深度氧化去除是环境领域的研究热点. 芬顿反应作为典型的高级氧化技术(AOPs)被广泛用于水中有机污染物的去除. 对于非均相芬顿反应, 催化剂表面Fe3+/Fe2+的循环是决定其活性的主要因素. Fe3+还原的关键在于接受额外电子, 因此电子是提升芬顿反应效率的关键. 传统非均相催化剂由于表面“惰性”, 限制了固液界面电子的传递, 导致Fe3+/Fe2+的循环效率处于较低的水平. 因此设计一种具有高效界面电子传递性能的催化剂对提高芬顿反应效率至关重要.
本文通过简易的酸处理法, 成功合成了富含缺陷的NH2-UiO-66 (d-NU)材料, 并将其用于水中有机污染物的去除. 核磁共振氢谱(1H NMR)、热重分析(TG)、傅里叶红外光谱(FTIR)和X射线吸收精细结构(EXAFS)等多种表征证明了酸处理诱导NH2-UiO-66上缺陷结构的形成. 光电流、电化学阻抗和时间分辨瞬态荧光光谱结果表明, 缺陷结构的形成可有效促进光生电子-空穴的分离. 与不含缺陷的NH2-UiO-66(NU)相比, d-NU在光芬顿氧化过程中表现出更优的4-CP去除效率, 其降解动力学速率常数是NU的11倍, 极大地加速了4-CP的去除进程. 实验及理论计算结果表明缺陷的形成破坏了Zr配位结构的几何对称性, 导致Zr位点电荷密度的不对称分布. 该不对称结构有利于Fe3+富集到Zr-O簇上, 并通过电子-金属-载体相互作用(EMSI)形成Zr‒O‒Fe桥键, 促进催化剂固液界面电子的传输, 提高催化剂界面Fe3+/Fe2+的循环效率. 实际应用实验结果表明, 在d-NU/Fe3+/H2O2光芬顿体系中, 环境水体中常见无机离子对4-CP的降解影响很小. 同时, d-NU/Fe3+/H2O2光芬顿体系能够对多种有机污染物保持较高的去除效率, 且催化活性在经过10次循环后没有明显的衰减, 说明d-NU具有较好的抗离子干扰性、降解多种污染物的普适性和结构稳定性. 通过液相色谱-质谱监测确定了4-CP的降解途径, 并通过毒理学模拟4-CP及其降解生成中间体的生物毒性, 结果表明, 4-CP降解过程中形成的中间体的综合毒性低于4-CP.
综上, 本研究揭示了MOF基芬顿催化剂中金属氧簇的配位关系对芬顿反应的作用机制, 提出了富含缺陷的MOFs与Fe3+之间电子转移的作用机制, 为进一步开发高效芬顿催化剂提供了新思路.

关键词: 缺陷, NH2-UiO-66, 三价铁还原, 电子-金属支撑作用, 芬顿反应

Abstract:

The inefficient reduction of Fe3+ and activation of H2O2 in the Fenton reaction severely limit its application in practical water treatment. In this study, we developed defective NH2-UiO-66 (d-NU) with coordinated unsaturated metal sites by adjusting the coordination configuration of Zr, creating a solid-liquid interface to facilitate Fe3+ reduction and the sustainable generation of •OH from H2O2 activation. The d-NU/Fe3+/H2O2/Vis system demonstrated highly efficient removal of various organic pollutants, with a rapid Fe2+ regeneration rate and exceptional stability over ten cycles. The degradation rate constant of d-NU (0.16112 min-1) was 11 times higher than that of NH2-UiO-66 (NU) (0.01466 min-1) without defects. Characterization combined with density functional calculations revealed that defects induced coordination unsaturation of the Zr sites, leading to in situ electron-metal-support interactions between Fe3+ and the support via Zr-O-Fe bridges. This accumulation of electrons from the unsaturated Zr sites enabled the adsorption of Fe3+ at the solid-liquid interface, promoting the formation of Fe2+ across a wide pH range with a reduced energy barrier. This study introduces a promising strategy for accelerating Fe3+ reduction in the solid-liquid interfacial Fenton process for the degradation of organic pollutants.

Key words: Defect, NH2-UiO-66, Fe3+ reduction, Electron-metal-support interactions, Fenton reaction