Biomass-Derived Porous Carbon Modified with Black Phosphorus Nanosheets as Effective Sulfur Host for Lithium-Sulfur Batteries

Abstract

The shuttle effect and slow oxidation-reduction reactions of the cathode in lithium-sulfur batteries limit its practical application and development. Herein, porous carbon derived from pollen modified by black phosphorus nanosheets (BP/N−C) have been synthesized and utilized as a sulfur host in Li−S batteries. From the compositional outlook, the biomass-derived carbon forms a unique three-dimensional skeleton structure, exhibiting excellent properties, such as high porosity and high conductivity. Upon modified with black phosphorus, the BP/N−C composite materials demonstrate enhanced adsorption ability and catalytic activity toward lithium polysulfides (LiPSs). The BP/N−C/S cathode electrode presents a high initial specific discharge capacity of 1009.6 mAh g⁻¹ and a low capacity decay rate of 0.08% per cycle during 150 cycles at 0.2 C rate. Besides, the BP/N C/S cathode electrode exhibits the superior rate performance (508 mAh g⁻¹ at 5 C).