文献类型：期刊文献

英文题名：Computationally revisiting pH- and ligand-dependence of Fenton reaction selectivity and activity in aqueous solution

作者：Liu, Ying[1,2];Hu, Peijun[1,2,3,4];Wang, Haifeng[1,2]

机构：[1]East China Univ Sci & Technol, Ctr Computat Chem, State Key Lab Green Chem Engn & Ind Catalysis, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Res Inst Ind Catalysis, Shanghai 200237, Peoples R China;[3]Queens Univ Belfast, Sch Chem & Chem Engn, Belfast BT9 5AG, North Ireland;[4]ShanghaiTech Univ, Sch Phys Sci & Technol, Shanghai 201210, Peoples R China

年份：2025

卷号：27

期号：24

起止页码：12929

外文期刊名：PHYSICAL CHEMISTRY CHEMICAL PHYSICS

收录：;EI(收录号：20252418600096);WOS:【SCI-EXPANDED(收录号:WOS:001502867200001)】；

基金：This project was supported by National Key Research and Development Program of China (2021YFA1500700), the NSFC (22202069 and 21873028), and the Fundamental Research Funds for the Central Universities.

语种：英文

外文关键词：Binding sites - Degradation - Deprotonation - Free radical reactions - Oxidation - Reaction intermediates - Reaction kinetics

摘要：The Fe-based Fenton reaction is pivotal in generating reactive oxidative species (ROS) such as OH center dot radicals and iron-oxo (FeO2+)-O-IV to degrade wastewater pollutants, yet the selectivity origin of ROS remains debated. Using ab initio molecular dynamics and microkinetic modeling, we investigate the atomic-level Fenton reaction mechanism catalyzed by the Fe-III-complex [(Cl-)(3)Fe-III(H2O)(3)] in aqueous solution to quantify ROS activity and selectivity. We demonstrate that Fe-III is first reduced to Fe(II)via H2O2 deprotonation and OOH center dot release, after which Fe-II enables O-O bond cleavage of a second H2O2, producing OH center dot and Fe-III-OH-. The Fe-III-OH- intermediate can either be protonated or oxidized by OH center dot to form (FeO2+)-O-IV, driving a pH-dependent selectivity switch: OH center dot dominates at pH < 2.5, while (FeO2+)-O-IV prevails at pH > 2.5. Moreover, Fe-complex ligands regulate Fe-III-OH- stability and affect ROS selectivity/activity by modulating the OH intermediate binding strength, which linearly correlates with the O-O bond cleavage barrier and OH center dot desorption kinetics. Comparing homogeneous Fe-complex catalysis to the state-of-the-art heterogeneous FeOCl, we highlight that optimized OH binding at the Fe-II center dot center dot center dot Fe-III dual site of FeOCl facilitates O-O bond cleavage while ensuring efficient OH center dot desorption, leading to higher activity. These findings provide atomic-level insights into pH-dependent ROS selectivity and ligand effects, advancing our understanding of both homogeneous and heterogeneous Fenton catalysis.