3D hierarchically porous carbon derived from asphalt via salt template strategy for high-performance aqueous zinc-sulfur batteries

Conductive carbon materials have great potential as sulfur host for zinc-sulfur batteries, and their microstructures have a significant impact on the electrochemical activity. Herein, conductive carbon materials with different microstructures were synthesized from asphalt through a two-step annealing procedure using potassium citrate and sodium chloride as the templates. Among these materials, three-dimensional hierarchically porous carbon (3DPC) offers superior ionic and electronic conductivity for zinc-sulfur batteries due to its unique microstructure. The zinc-sulfur battery using S@3DPC as the cathode exhibits lower polarization (1.13 V) and excellent rate performance (582.2mAh g- 1 at 5.0 A g- 1). A high discharged capacity of 322.4mAh g- 1 can still be maintained even after 500 cycles at 5 A g- 1.