Mesoporous carbon from biomass: one-pot synthesis and application for Li–S batteries†
Abstract
A new one-pot and activation-free method was developed to synthesize high porosity biomass-derived carbon (HPBC) with uniform mesopores through sol–gel route. The as-prepared HPBC material possesses high surface area up to 949.85 m2 g−1 and high pore volume of 3.14 cm3 g−1. Cathodes with sulfur content of 81.29 wt% for Li–S batteries were prepared using the HPBC as a conductive matrix and a certain amount of space was preserved to accommodate the volume change during lithiation. When evaluated for electrochemical properties, the uniform pore structure of the HPBC afforded superior cyclability and rate performance for the Li–S batteries. An initial capacity of 922 mA h g−1 and a reversible capacity of 683 mA h g−1 were delivered after 100 cycles at a current density of 0.5 C. Specifically, a reversible capacity of 483 mA h g−1 was retained over 300 cycles at a current density of 1 C.