Implanting heterogeneous Ni₂P/CoP catalysts in MOF–derived carbon arrays with multifunctional catalytic sites for Li–SeS₂ batteries

SeS₂ possesses the combined merits of S and Se with considerable capacity and high electronic conductivity, but is still hindered by a shuttle effect of lithium polysulfides/polyselenides and sluggish conversion kinetics. Herein, high–efficiency heterogeneous Ni₂P/CoP catalysts implanted into MOF–derived carbon arrays (Ni₂P/CoP@NC) are developed to simultaneous immobilize polysulfides/polyselenides and regulate their conversion. The Ni₂P/CoP catalysts with hollow and hierarchical structures extremely expose abundant catalytic and adsorption sites for LiPS/LiPSe conversion reaction. Meanwhile, the strong chemical binding of Ni₂P/CoP towards LiPSs/LiPSes through Ni–S, Ni–Se, Co–S and Li–P bonds favors for the regulation of polysulfide/polyselenide conversion. The DFT calculation results corroborate the heterogeneous Ni₂P/CoP interface provides depressed lithium–ion diffusion barriers to promote the polysulfide/polyselenide conversion kinetics. Benefiting from abundant catalytic and adsorption sites, strong chemical binding towards LiPSs/LiPSes and depressed lithium–ion diffusion barriers, the Ni₂P/CoP@NC catalysts enable considerable specific capacities, superior rate performance and stable cycling performance for Li–SeS₂ batteries.