Rational Construction of Fluffy CNT on Binary FeCo‐NC as High‐Efficiency S Host for Li−S Battery

Abstract

AbstractDeveloping functional porous carbon materials that are efficient for hosting S and catalytically converting Li polysulfide (LiPS) is of great importance to ease the LiPS shuttle effect, which is the main obstacle against the practical applications of Li−S batteries. Herein, we developed a porous binary FeCo‐NC material functionalized by dual‐site catalytic FeCo species and delicately introduced carbon nanotube (CNT) forest on FeCo‐NC surface. The successful decoration of highly dispersed binary Fe and Co species and heavily introduced N species up to 10 at.%, are critical to improve the quality of host interfaces for high‐efficiency anchoring/conversion of polar LiPS and electrolyte wetting. The fluffy CNT forest on particulate FeCo‐NC can serve as highway for electron conducting and reservoir for confining S/LiPS when physically stacked. Electrochemical measurements indicated binary FeCo‐NC/CNT composite serving as host for a 70 wt.% S loading. It showed enhanced absorption and conversion kinetics of LiPS, and improved rate capability and stability of Li−S half‐cell.