摘要
The polysulfide shuttle effect critically hinders lithium-sulfur(Li-S)battery development,therefore,the design of heterogeneous interface engineering with“adsorption-catalysis”functions for polysulfide conversion has garnered considerable attention.However,the exploration of the intricate relationship between key electronic properties and catalytic activity at such interfaces remains a challenge.Additionally,a comprehensive understanding of the thermodynamic growth mechanisms for heterostructure materials is lacking.Herein,a Ni-based homologous structure was precisely constructed via thermodynamic control,with a specific focus on optimizing the interface design.The theoretical results show that the heterostructures with adjustable composition realize the appropriate upward shift to the D-band,improving the affinity towards polysulfide,and further reducing the reaction energy barrier.On this basis,the relationship between interface design and the D-band center,as well as catalytic performance,was established.Specifically,M-Ni_(3)Fe/Ni_(3)ZnC_(0.7)accomplishes the electron enrichment at the interface,supporting the further diffusion of polysulfides,and lowering the Li-S bond energy,performing the bidirectional catalytic transformation of polysulfides.As a result,the Li-S batteries with the cathode of M-Ni_(3)Fe/Ni_(3)ZnC_(0.7)/S deliver rate performances of discharge capacity of 514 mA h g^(−1)at 5.0 C.This understanding of the D-band and interfacial design provides a framework for Li-S catalyst optimization.
基金
supported financially by the National Natural Science Foundation of China(52172242,22109135,52371237)
the Science&Technology Talents Lifting Project of Hunan Province(2023TJ-Z32)
the Hunan Provincial Education Office Foundation of China(20B570,23B0126)
the Natural Science Foundation of Hunan Province(2021JJ30659,2022JJ40423)
the Postgraduate Scientific Research Innovation Project of Hunan Province(QL20230146).
