物理化学学报2025，Vol.41Issue(12)：122-133,12.DOI:10.1016/j.actphy.2025.100160
利用飞秒瞬态吸收光谱研究pH值对质子化COF光催化H2O2生成的影响
Understanding the effect of pH on protonated COF during photocatalytic H2O2 production by femtosecond transient absorption spectroscopy
摘要
Abstract
Covalent organic frameworks(COFs),recognized for their precisely tunable microstructures and high surface area,are promising photocatalysts for H2O2 production.However,the critical influence of pH on the stability of COF during the photocatalytic H2O2 production remains poorly understood.In this work,the photocatalytic H2O2 production performance of an imine-linked COF is significantly enhanced through a simple protonation strategy.Crucially,the protonated COF exhibits excellent stability under weakly acidic conditions(pH≥3),but undergoes irreversible hydrolyzed under strongly acidic conditions(pH<3).The protonation occurs specifically at the nitrogen atoms of imine units and serves a dual function:it suppresses ultrafast charge recombination(as revealed by femtosecond transient absorption spectroscopy)and directly provides a proton source for H2O2 generation.Moreover,fluoride ions(F-)are introduced into the photocatalytic system to further improve the photocatalytic H2O2 production rate.The strong electronegativity of F-facilitates electron transfer from COF to F-,thus realizing the spatial separation of photogenerated carriers.Mechanistic studies confirm that H2O2 production follows a two-electron oxygen reduction reaction pathway.These findings elucidate the pH-dependent stability and activity of protonated COFs,provide fundamental insights into charge carrier dynamics,and establishe design principles to develop highly efficient and stable COF-based photocatalysts for solar-driven H2O2 generation.关键词
共价有机框架/结构稳定性/质子化/氟离子表面修饰/飞秒瞬态吸收光谱Key words
Covalent organic frameworks/Structural stability/Protonation/Fluoride ion surface modification/Femtosecond transient absorption spectroscopy分类
化学化工引用本文复制引用
Xin Zhou,Yiting Huo,Songyu Yang,Bowen He,Xiaojing Wang,Zhen Wu,Jianjun Zhang..利用飞秒瞬态吸收光谱研究pH值对质子化COF光催化H2O2生成的影响[J].物理化学学报,2025,41(12):122-133,12.基金项目
This work was supported by National Natural Science Foundation of China(52202375,22469001,22409181),the Natural Science Foundation of Hubei Province of China(2022CFA001,2025AFB631),Ordos Institute of Technology Research Programs(KYQN25Z012,KYYB2023014),and the Scientific Research Funds at China University of Geosciences(Wuhan)(Project No.2025034)and Natural Science Foundation of Inner Mongolia Autonomous Region of China(2025QN05107,2025ZDLH002). 国家自然科学基金(52202375,22469001,22409181),湖北省自然科学基金(2022CFA001,2025AFB631),鄂尔多斯应用技术学院科研项目(KYQN25Z012,KYYB2023014),中国地质大学(武汉)中央高校基本科研业务费专项资金(项目编号 2025034)以及内蒙古自治区自然科学基金(2025QN05107,2025ZDLH002)的资助 （52202375,22469001,22409181）
