Better and greener: Chitin nanofibers mixed with polystyrene nanoparticles are tuned to activated hierarchically porous carbon. The higher degree of mesopore uniformity within the carbon material results in amorphous carbon removal and exposure of the graphene basal planes. Very high capacitance is observed, even though the material is not N-doped.
The applicability of chitin-based carbon as a supercapacitor electrode material was investigated by adjusting its pore structure through polystyrene latex templating, without significant N doping. 2,2,6,6-tetramethylpiperidinyloxy (TEMPO)-oxidized chitin nanofibers were mixed with polystyrene latex, hydrothermally treated at 220 °C, carbonized, and activated using KOH at 800 °C, yielding activated hierarchical porous carbon. The variation of both polystyrene latex amount and carbonization temperature resulted in changes in the surface area and pore structure, which dictated the degree of pore uniformity and activation efficiency. The pore structure affected activation by allowing the selective removal of amorphous carbon, exposing the basal plane carbon, resulting in higher specific capacitance. By making activated hierarchical porous carbon more conducive to activation, specific capacitance of 567 F g−1 at 0.5 A g−1 was achieved, with no loss in performance after 10000 charge–discharge cycles.Zum Volltext