Development of Sn^(2+)-based oxyfluoride photocatalyst with visible light response of ca.650 nm via strengthened hybridization of Sn 5s and O 2p orbitals  

作　　者：Yanpei Luo Xin Zhou jiangwei Zhang Yu Qia Zheng Lia Fuxiang Zhang Can Li 

机构地区：[1]State Key Laboratory of Catalysis,Dalian Institute of Chemical Physics,Chinese Academy of Sciences,Dalian National Laboratory for Clean Energy,The Collaborative Innovation Center of Chemistry for Energy Materials(iChEM),Dalian 116023,Liaoning,China [2]University of Chinese Academy of Sciences,Beijing 100049,China [3]College of Environment and Chemical Engineering,Dalian University,Dalian 116622,Liaoning,China

出　　处：《Journal of Energy Chemistry》2021年第12期385-390,I0009,共7页能源化学（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(NSFC)(22088102);supported by the National Natural Science Foundation of China(21633009,21633010,21925206);the Cooperation Fund of Dalian National Laboratory for Clean Energy(DNL201913);International Partnership Program of Chinese Academy of Sciences(121421KYSB20190025);the DICP foundation of innovative research(DICPI201927);Strategic Priority Research Pro-gram of Chinese Academy of Sciences(XDB17000000);support from Liaoning Revitalization Talents Program(XLYC1807241)。

摘　　要：The hybridization between the outmost s orbitals of metal(Bi^(3+),Sn^(2+),Pb^(2+),Ag^(+))and O 2 p orbitals has been widely employed to develop innovative semiconductors with upshift valence band as well as extended visible light response,but it is still challenging to obtain photocatalyst with absorption edge of above 550 nm.Here we report a novel Sn^(2+)-based oxyfluoride Sn_(2)TiNbO_6 F(STNOF)photocatalyst with a pyrochlore structure to exhibit an extended absorption edge to 650 nm and dual functionalities of both water reduction and oxidation.Density functional theory calculations suggest that the unprecedented broad-spectrum response of STNOF is mainly ascribed to the strengthened hybridization between O 2 p and Sn 5 s orbitals remarkably upshifting the valence band,which is caused by the distortion and compressive strain in the Sn06 F2 dodecahedron with second-order Jahn-Teller effect due to partial fluorine substitution.The structural distortion and compressive strain are experimentally confirmed by the Fourier-transformed extended X-ray absorption fine spectra.As probe tests of the photocatalytic functionalities,water reduction and oxidation half reactions were examined to see obvious H_(2)and O_(2)evolution under visible light irradiation.This work may provide an alternative strategy of developing extended visible light responsive semiconductors for promising solar energy conversion.

关 键 词：PHOTOCATALYST Visible light Water splitting DFT Structural characterizations 

分 类 号：O643.36[理学—物理化学] O644.1[理学—化学]