Confining Li2O2 in tortuous pores of mesoporous cathodes to facilitate low charge overpotentials for

• 作 者: Yin Zhou Yong Zhao Zhenjie Liu Zhangquan Peng Li Wang Wei Chen
• 机 构: Department of Chemistry,National University of Singapore,3 Science Drive 3,117543,Singapore;Institut
• 出 处: 能源化学
• 发表日期: 2021年4期
• 关键词: Lithium-oxygen CMK-8 cathode Charge overpotential Lithium superoxide Cycle perfo

Achieving low charge overpotentials represents one of the most critical challenges for pursuing high-performance lithium-oxygen(Li-O2)batteries.Herein,we propose a strategy to realize low charge over-potentials by confining the growth of lithium peroxide(Li2O2)inside mesoporous channels of cathodes(CMK-8).The CMK-8 cathode with tortuous pore structures can extend the diffusion distance of lithium superoxide(LiO2)in the mesoporous channels,facilitating the further reduction of LiO2 to lithium perox-ide(Li2O2)inside the pores and preventing them to be diffused out of the pores.Therefore,Li2O2 is trapped in the mesoporous channels of CMK-8 cathodes,ensuring a good Li2O2/CMK-8 contact interface.The CMK-8 electrode exhibits a low charge overpotential of 0.43 V and a good cycle life for 72 cycles with a fixed capacity of 500 mAh g-1 at 0.1 A g-1.This study proposes a strategy to achieve a low charge over-potential by confining Li2O2 growth in the mesoporous channels of cathodes.