Pauling-type adsorption of O_(2) induced by S-scheme electric field for boosted photocatalytic H_(2)O_(2) production  

作　　者：Shuang Zhou Da Wen Wei Zhong Jianjun Zhang Yaorong Su Aiyun Meng 

机构地区：[1]College of New Materials and New Energies,Shenzhen Technology University,Shenzhen 518118,China [2]Laboratory of Solar Fuel,Faculty of Materials Science and Chemistry,China University of Geosciences,Wuhan 430078,China

出　　处：《Journal of Materials Science & Technology》2024年第32期53-65,共13页材料科学技术(英文版)

基　　金：supported by the National Nature Science Foundation of China(Nos.22272110,22178224,and 22002091);the Fundamental Research Funds for Shenzhen Technology Uni-versity(No.20211063010047);the Guangdong Basic and Ap-plied Basic Research Foundation(Nos.2020A1515110873 and 2023A1515110535);the Shenzhen Science and Technology Pro-gram(No.20231127203830001).

摘　　要：The effective adsorption of oxygen(O_(2))molecules over photocatalysts is a critical step in promoting the performance of photocatalytic H_(2) O_(2) production.However,g-C_(3)N_(4) usually features a Yeager-type(side-on)adsorption configuration of O_(2) molecules,which causes the breaking of O-O bonds and severely hinders the H_(2) O_(2) production activity.Herein,we synthesized an oxygen-vacancy-rich TiO_(2-x)/g-(3)N_(4) step-scheme(S-scheme)heterojunction to regulate the oxygen adsorption configuration and improve the 2e-ORR se-lectivity of H_(2) O_(2) production.In-situ X-ray photoelectron spectroscopy(in-situ XPS)and density functional theory(DFT)calculations reveal that the S-scheme heterojunction is formed between TiO_(2-x) and g-(3)N_(4).The difference between their Fermi levels leads to the electron flow from g-(3)N_(4) to TiO_(2-x),which in-creases the electron-deficient sites in g-(3)N_(4).As a result,the cleavage of O-O bonds on the surface of g-(3)N_(4) is avoided and the oxygen adsorption configuration is tuned from Yeager-type to Pauling-type(end-on).Consequently,the photocatalytic H_(2) O_(2) production rate is dramatically improved to 1780.3μmol h-1,which is about 5 times higher than that of pristine g-(3)N_(4).This work paves a new way to tailor the oxygen adsorption configuration by rationally designing S-scheme heterojunction photocatalysts.

关 键 词：S-scheme heterojunction Hydrogen peroxide production Pauling-type oxygen adsorption Femtosecond transient absorption spectroscopy Two-electron oxygen reduction selectivity 

分 类 号：O64[理学—物理化学]