Synthesis of a Novel Petal-Shaped Biomass-Derived Carbon Material with Controlled Pore Structure and Nitrogen Content for Use in Supercapacitors

Controllably adjusting the porosity and the heteroatom content has become extremely attractive for increasing the energy storage capacity of carbon materials. In this work, petal-shaped N-doping carbon materials with super-high specific surface area (2752 m(2) g(-1)) and enriched micropores (90.1 %) have been synthesized by using renewable spikes of terminalia catappa as raw materials via a facile and feasible method. The results confirmed that the prepared N-doping carbon material exhibits outstanding electrochemical performances. The specific capacitance reaches up to 503 F g(-1) at 0.5 A g(-1) and 306 F g(-1) at 50 A g(-1); cycling stability maintains 100.2 % after 10000 cycles. The fabricated symmetric supercapacitor shows an attractive energy density of 30.5 W h Kg(-1) at a power density of 492.4 W Kg(-1) in 1 M Na2SO4 electrolyte. Moreover, this study opens up a new way to enhance the micropore proportion and N content of carbon materials and displays the unique petal-shaped nano-flakes morphology that can maximally expose the surface of carbon materials.