ZnIn_(2)S_(4)/MOF S-scheme photocatalyst for H_(2)production and its femtosecond transient absorption mechanism  

作　　者：Jiajie Cai Bowen Liu Shumin Zhang Linxi Wang Zhen Wu Jianjun Zhang Bei Cheng 

机构地区：[1]State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan University of Technology,Wuhan 430070,China [2]Hunan Key Laboratory of Applied Environmental Photocatalysis,Changsha University,Changsha 410022,China [3]Laboratory of Solar Fuel,Faculty of Materials Science and Chemistry,China University of Geosciences,68 Jincheng Street,Wuhan 430078,China [4]Department of Chemical Engineering,Ordos Institute of Technology,Ordos 017000,China

出　　处：《Journal of Materials Science & Technology》2024年第30期183-193,共11页材料科学技术(英文版)

基　　金：supported by the National Key Research and Development Program of China(Nos.2022YFB3803600 and 2022YFE0115900);the National Natural Science Foundation of China(Nos.22208332,22278324,52073223,22238009,51932007,22361142704);the Natural Science Foundation of Hubei Province of China(No.2022CFA001);the Key R&D Program Projects in Hubei Province(No.2023BAB113).

摘　　要：Photocatalytic water splitting is a popular pathway for H_(2)evolution,but the slow water oxidation greatly hampers the overall activity.To harness photogenerated holes in an efficient and lucrative way,the wa-ter oxidation reaction is replaced by selective oxidation of organic compounds to achieve simultaneous production of H_(2)and value-added chemicals.Herein,an alternative tactic is reported where an organic compound(benzylamine,BA)not only serves as the precursor for N-benzylidene-benzylamine(NBBA)production but also provides hydrogen sources for H_(2)evolution,achieving the goal under anhydrous conditions.This process is realized using an S-scheme photocatalyst composed of ZnIn_(2)S_(4)and the UiO-66-NH_(2)(U6N)metal-organic framework(MOF).The S-scheme carrier transfer mechanism was validated by in-situ irradiated X-ray photoelectron spectroscopy(ISI-XPS)and femtosecond transient absorption(fs-TA)spectroscopy.With increased carrier efficiency and reinforced redox power endowed by the S-scheme heterojunction,the composite performed better than ZnIn2 S4 and MOF.The performance was further ameliorated by Pt-cocatalyst modification,achieving an H_(2)production rate of 5275μmol h^(-1)g^(-1)as well as BA conversion of 94.3%with 99.3%NBBA selectivity.Mechanistic studies reveal that BA is ini-tially oxidized to carbon-centered radicals and further to imines along with the release of protons.The imine reacts with another BA molecule to form NBBA,while the protons are reduced to H_(2).This work provides new insights into concurrent photocatalytic H_(2)production and selective organic oxidation from organic amines using S-scheme photocatalysts.

关 键 词：Photocatalysis S-scheme heterojunction Hydrogen production Selective oxidation BENZYLAMINE Femtosecond transient absorption 

分 类 号：O62[理学—有机化学]