An integrated cathode with bi-functional catalytic effect for excellent-performance lithiu

An integrated cathode with bi-functional catalytic effect for excellent-performance lithium-sulfur

batteries

Mengmeng Zhen;Xintao Zuo;Juan Wang;Cheng Wang

【期刊名称】《纳米研究（英文版）》 【年(卷),期】2019(012)005

【摘要】The high energy density of lithium-sulfur batteries (LSBs) is mainly based on the complex redox reactions and phase conversions.The sluggish redox kinetics and the large accumulation of soluble polysulfides in the electrolyte leads to low sulfur utilization and serious shuttle effect.Herein,an integrated sulfur cathode is constructed through a facile and large-scale method.It is composed of sulfur-N,S doped bamboo like CNTs@Co3S4 (NSC@Co3S4) composites on polypropylene

separator.The

immobilized

polysulfides

on

the

NSC@Co3S4 surface are further reduced/oxidized during the discharge/charge process via the efficient bi-functional catalytic effect of

NSC@Co3S4,resulting

in

the

rapid

conversion

of

LiPSs.Consequently,the integrated sulfur cathode delivers a high initial reversible capacity of 1,473.6 mAh·g-1 at 0.2 C and a high specific capacity of 979 mAh·g-1 at 1 C after 500 cycles as well as excellent cycling stability for 1,000 cycles with a high specific capacity of 362.5 mAh·g-1 at 5 C,which are superior to reported similar host materials.