181 / 2022-02-14 15:25:49

In situ perfusing Sb particles into porous N-doped carbon microspheres and their electrochemical properties in potassium ion batteries

Potassium ion battery, Antimony, electrolyte optimization, hierarchical structure.

Energy Science and Technology > 11. Chemical Energy Storage Engineering

ABSTRACT: Antimony-based materials with low platform and high theoretical capacity have been considered as a promising candidate of anode material for economical and high-performance potassium ion batteries (PIBs) in the recent decades. Unfortunately, they are still affected by the sluggish kinetics and poor cycle stability, meanwhile, the large radius of the K⁺ ion leads to the aggregation of particles. Herein, we developed an in-situ perfusing method to construct Sb nanoparticles into the hierarchical porous N-doped carbon (HPNC) microspheres restriction structure, which was proved to be a reasonable and efficient way to enhance the electrochemical properties. Meanwhile, it was acknowledged that electrolyte optimization (KPF₆ and KFSI) exerted significant influence on greatly enhancing the electrochemical performance. With the hierarchical porous structure and the electrolyte composition design, Sb@HPNC exhibits an outstanding reversible capacity of up to 507 mAh g^-1 at a current density of 0.1 A g^-1 over 100 cycles and excellent long-cycle stability of 262 mAh g^-1 at 1.0 A g^-1 over 700 cycles. We expect this work can offer a reference for the development and exploration of advanced alloy-type electrodes for PIBs.