Corncob cellulose-derived hierarchical porous carbon for high performance supercapacitors

Abstract

Cellulose texture in biomass is a desired renewable carbon source to prepare activated carbon with abundant porous structure and high specific surface area. However, the cellulose fractionation/separation from biomass is still a challenge. Here, corncob cellulose-derived hierarchical porous carbon has been fabricated successfully via a facile mechanical fragmentation and sieving pretreatment with subsequent carbonization and activation. The microstructural analyses show that the morphologies and textures of the corncob-derived carbon are highly depended on the corncob basic components such as cellulose, hemicellulose and lignin. Among the corncob-derived carbons, the corncob cellulose-derived hierarchical porous carbon (CPA-35-150) exhibits the largest specific surface area (1940.6 m2 g−1) and decent pore size distribution. Consequently, the high specific capacitance of 208.5 F g−1 at 1 A g−1 and outstanding rate capability are realized. Also, CPA-35-150 shows good cycling stability with 97.2% capacitance retention after 20,000 cycles under 10 A g−1.