Synthesis and application of Salacca peel based hierarchical porous carbons as cathodes for lithium sulfur battery

Abstract

Hierarchical porous carbons (HPCs) with different structures from micropores to macropores hierarchical pores were synthesized from biomass waste salacca peels via K2CO3 activation process. HPCs with high surface area of 2234 m2/g and pore volume of 1.25 cm3/ were obtained at K2CO3/carbon ratio higher than 3 and activation temperature of 800 C. Carbon/Sulfur (C/S) composites were then prepared with a high sulfur content of 62 wt%, as confirmed by TGA results. The composites were then used as cathodes for lithium sulfur (LiS) batter. High specific discharge capacities of more than 780 mAh/g were shown by the C/S composites at current density of 0.5 C-rate. After 500 cycles at 0.5 C, a high discharge capacity of 496 mAh/g was achieved, revealing excellent capacity retention.