Understanding Bonding Nature of α-Keggin Polyoxometalates[XW_(12)O_(40)]^(n−)(X=Al,Si,P,S):A Generalized Superatomic Perspective  

作　　者：Rui Li Yulei Shi Famin Yu Rui Wang Haitao Yan Boon K.Teo Zhigang Wang 

机构地区：[1]Department of Physics,Capital Normal University,Beijing 100048,China [2]Key Laboratory of Material Simulation Methods&Software of Ministry of Education,College of Physics,Jilin University,Changchun 130012,China [3]Institute of Atomic and Molecular Physics,Jilin University,Changchun 130012,China [4]State Key Laboratory for Physical Chemistry of Solid Surfaces,College of Chemistry and Chemical Engineering,Xiamen University,Xiamen 361005,China [5]Institute of Theoretical Chemistry,College of Chemistry,Jilin University,Changchun 130012,China

出　　处：《Energy & Environmental Materials》2024年第6期176-183,共8页能源与环境材料（英文）

基　　金：supported by the National Natural Science Foundation of China(under grant numbers 12174272 and 11974136)。

摘　　要：α-Keggin polyoxometalates(POMs)[XW_(12)O_(40)]^(n−)(X=Al,Si,P,S)are widely used in batteries owing to their remarkable redox activity.However,the mechanism underlying the applications appears inconsistent with the widely accepted covalent bonding nature.Here,first-principles calculations show that XW_(12)are core–shell structures composed of a shell and an XO_(4)^(n−)core,both are stabilized by covalent interactions.Interestingly,owing to the presence of a substantial number of electrons in W_(12)O_(36)shell,the frontier molecular orbitals of XW_(12)are not only strongly delocalized but also exhibit superatomic properties with high-angular momentum electrons that do not conform to the Jellium model.Detailed analysis indicates that energetically high lying filled molecular orbitals(MOs)have reached unusually high-angular momentum characterized by quantum number K or higher,allowing for the accommodation of numerous electrons.This attribute confers strong electron acceptor ability and redox activity to XW_(12).Moreover,electrons added to XW_(12)still occupy the K orbitals and will not cause rearrangement of the MOs,thereby maintaining the stability of these structures.Our findings highlight the structure–activity relationship and provide a direction for tailor-made POMs with specific properties at atomic level.

关 键 词：first principles molecular orbital POLYOXOMETALATE redox activity superatom 

分 类 号：TM910.4[电气工程—电力电子与电力传动]