Preparation and electrochemical performance of cellulose-based biomass-derived carbon materials

Biomass-derived carbon materials are regarded as an ideal precursor for activated carbon owing to their unique structure, widely used in energy storage applications. Porous biomass carbon materials were prepared by high-temperature carbonization and activation methods using corn stalk stem pith as the carbon source. The structures and morphology of biomass-derived carbon materials were also characterized and analyzed, and it was employed as the electrode material to study the electrochemical properties. The results showed that the specific surface area and pore volume increased with the increase of temperature under the action of the same activator. The activation degree of carbon materials by different activators showed obvious differences under the same temperature conditions, and the structure and properties of the carbon materials obtained by sodium hydroxide activation were better than those obtained by sodium bicarbonate activation. When the temperature was fixed at 900 ℃, the carbon materials obtained by sodium hydroxide activation showed the best structural characteristics and electrochemical properties, with the specific surface area up to 532.881 m2·g-1 and the microporous volume accounting for 76.266% of the total pore volume. By cyclic voltammetry test, the specific capacity was 139 F·g-1 at a scan rate of 10 mV·s-1, and the electrochemical impedance was much smaller than the impedance of the product obtained by sodium bicarbonate activation. Meanwhile, the specific capacity remained basically unchanged after 1000 cycles of charging and discharging, with excellent cycling stability and electrochemical performance. The relevant results provide a new way for the efficient utilization and functionalization of biomass resources.