Heat-treatment-assisted approach towards scalable synthesis of mesoporous carbons for high-performance lithium-sulfur battery

Abstract

A heat-treatment-assisted approach towards scalable synthesis of mesoporous carbons by direct solid-solid mixing of microcrystalline cellulose (MCC) and nano-sized SiO2, subsequent pyrolysis and SiO2 removal process, was reported in this study. The obtained mesoporous carbon presented a well-defined mesopore structure with high surface area and large mesopore size. During synthesis, MCC underwent structural relaxation process before degradation, which could provide a capillarity condensation force inducing the imprint of mesopore on final carbons. Due to the proper structure, the as-prepared mesoporous carbon showed prominent performance as sulfur host for lithium-sulfur (Li-S) battery, exhibiting a high reversible capacity of 860 mA h g−1 at 0.5 C after 200 cycles, and exceptional rate capability with 600 mA h g−1 at 5.0 C.