Abstract
High-energy-density Li-S batteries are sub-jected to serious sulfur deactivation and short cycle lifetime caused by undesirable polysulfide shuttle effect and frantic lithium dendrite formation.In this work,a controllable cage-confinement strategy to fabricate molybdenum car-bide(MoC)nanoclusters as a high-efficient sulfiphilic and lithiophilic regulator to mitigate the formidable issues of Li-S batteries is demonstrated.The sub-2 nm MoC nan-oclusters not only guarantee robust chemisorption and fast electrocatalytic conversion of polysulfides to enhance the sulfur electrochemistry,but also homogenize Li+flux to suppress the lithium dendrite growth.As a consequence,the MoC-modified separator endows the batteries with boosted reaction kinetics,promoted sulfur utilization,and improved cycling stability.A reversible capacity of 701 mAh·g-1 at a high rate of 5.0C and a small decay rate of 0.076％per cycle at 1.0C over 600 cycles are achieved.This study offers a rational route for design and synthesis of bifunctional nanoclusers with both sulfiphilicity and lithiophilicity for high-performance Li-S batteries.
基金项目
research funds from the National Natural Science Foundation of China(52272239)
中央高校基本科研业务费专项(D5000210894)
中央高校基本科研业务费专项(3102019JC005)
Analytical & Testing Center of Northwestern Polytechnical University for TEM analysis()
NETL
NSTL
万方数据