Silica-Confined Activation for Biomass-Derived Porous Carbon Materials for High-Performance Supercapacitors

Biomass-derived porous carbons have become the most competitive electrode materials for energy storage devices due to their renewable and sustainability properties. However, the obtained porous carbon by direct pyrolysis of biomass generally has a low surface area and poor porosity, limiting its electrochemical performance. Herein, a silica-confined activation strategy was used to prepare porous carbon with typical biomass microcrystalline cellulose (MCC) as carbon precursor (noted as MCPC). In this approach, the MCC was coated by silica to create a confined condition, in which the in-situ generated gases of e. g., CO2, H2O, etc. can diffuse into the porous space to active the carbon framework, resulting in large specific surface area and rich mesoporous structure. Moreover, the influences of silica amount and pyrolysis temperature on MCPC was also investigated. As electrode materials, the MCPC showed excellent electrochemical performance with outstanding stability and high specific capacitance, endowing it with high promising for energy storage.