ZIF-67 encapsulated CoNiSe2 particles anchored on honeycomb structure as high-performance anode materials for sodium-ion battery

Abstract

Metal selenides show great potential as an anode for sodium-ion batteries (SIBs). However, they suffer from huge volume change and sluggish kinetics. The binary-metal selenide of CoNiSe2 is proposed to be embedded in a honeycomb-like conductive structure decorated with ZIF-67 pyrolytic carbon coating (HC-ZC@CNS). Even at 10 A g−1, the as-prepared HC-ZC@CNS electrodes exhibit a remarkable Na+ storage capability of 258.3 mA h g−1 when employed in SIBs. The improving electrochemical behavior is attributed to the skilled structure's excellent conductivity, capacitive contribution, better Na+ diffusion coefficient, and the synergetic effect between Co and Ni. This design provides a new paradigm for enhancing SIBs performances.