Energy Band-Modulated SnO Anodes with Improved Rate Capacity and Initial Coulombic Efficiency for Sodium-Ion Batteries

Abstract

An efficient interface and composition modification strategy is proposed to significantly increase the rate capacity and initial Coulombic efficiency (ICE) of SnO anodes via energy band structure modulation for Na-ion batteries (SIBs). The asfabricated SnO@Bi@C material with Bi nanocrystals homogeneously dispersed on and around the SnO surface is prepared by an electrospinning method. The excellently dispersed Bi nanocrystals realize an effective interface contact with SnO and Na 2 O, which effectively lowers the electron conduction barriers and promotes sodium-ion release and transport upon the desodiation process, increasing the rate capacity and ICE of the SnO anode. The prepared SnO@Bi@C exhibits a much higher rate capacity up to 10 A g −1 , except an improved ICE of 80.