In-situ rooting ZnSe/N-doped hollow carbon architectures as high-rate and long-life anode materials for half/full sodium-ion and potassium-ion batteries

Abstract ZnSe nanoparticles@ nitrogen-doped hollow polyhedron composite (ZnSe NP@NHC) was synthesized through the convenient pyrolysis of ZIF-8 precursor and subsequent selenization process. The ZnSe nanoparticles decorated on hollow carbon polyhedron endow the overall electrode with abundant exposed active sites and enhanced conductivity, which could buffer the volume expansion and improve the charge-transfer kinetics. In addition, nitrogen doping further increase the interfacial adsorption between carbon and active species. These features significantly enhanced the electrochemical performances of ZnSe NP@NHC anode material in ether-based electrolyte for Potassium-ion batteries (PIBs) and Sodium-ion batteries (SIBs). The composite exhibits superior performances when applied as anode for KIBs (∼132.9 mA h g−1 during 1200 cycles at 0.1 A g−1 in PIBs) and for SIBs (160.7 mAh g−1 at 10 A g−1, 250.8 mAh g−1 during 1300 cycles at 1 A g−1 with high initial CE of 99%). Electrochemical mechanism was investigated via XRD patterns and kinetics analysis, which reveals that pseudocapacitance contribution is one of the key reasons for remarkable rate capability. The PB//ZnSe NP@NHC Sodium-ion full cells were assembled successfully and could stably work for over 100 cycles. These results uncover the promising potential of ZnSe NP@NHC towards PIBs and SIBs with high performances.