Stabilizing nickel sulfide nanoparticles with an ultrathin carbon layer for improved cycling performance in sodium ion batteries
metal sulfides, sodium-ion batteries, composite, carbon coating layer, cycling stability
ABSTRACT Nanostructured metal sulfides are potential electrode materials for sodium-ion batteries; however, they typically suffer from very poor cycling stability due to large volume changes and dissolution of discharge products. Herein we propose a rational material design strategy for sulfide-based materials to address these problems. Taking nickel sulfide (NiSx) as an example, we demonstrated that its electrochemical performance can be dramatically improved by confining the NiSx nanoparticles in a percolating conductive carbon nanotube network, and stabilizing them with an ultrathin carbon coating layer. The carbon layer serves as a physical barrier to alleviate the effects of both the volume change and dissolution of active materials. The hybrid material exhibited a large reversible specific capacity of >500 mAh/g and excellent cycling stability over 200 cycles. Given the traditionally problematic nature of NiSx as a battery anode material, we believe that the observed high performance reported here reflects the effectiveness of our material design strategy.
Tsinghua University Press
Feipeng Zhao,Qiufang Gong,Brian Traynor,Duo Zhang,Jiaojiao Li,Hualin Ye,Fengjiao Chen,Na Han,Yeyun Wang,Xuhui Sun,Yanguang Li, Stabilizing nickel sulfide nanoparticles with an ultrathin carbon layer for improved cycling performance in sodium ion batteries. NanoRes.2016, 9(10): 3162–3170