Pristine organo-imido polyoxometalates as an anode for lithium ion batteries

Abstract

Here we have designed a strategy to improve the electronic conductivities of polyoxometalates (POMs) via property-oriented organic grafting for use in lithium-ion batteries (LIBs). POMs usually exhibit limited electronic conductivity that hinders their use in electronic applications. Organic grafting of POMs defines a valuable path for improving electronic conductivities of POMs, due to the enhanced metal to ligand charge transfer (MLCT) via d–π electronic interactions, and results in their feasible application in LIBs. Comparative practical and theoretical study of the effect of functional groups revealed that grafting of the remote electron withdrawing group (–SCN) on POMs via organo-imidoylization along with lower values of lowest unoccupied molecular orbitals (LUMO) results in an enhanced performance as Mo₆–SCN shows initial discharge capacity of ∼1678 mA h g⁻¹ with ∼85% capacity retention and coulombic efficiency ∼100% after 100 cycles.