Biowaste-originated heteroatom-doped porous carbonaceous material for electrochemical energy storage application

Here, a unique heteroatom-doped spongy carbonaceous material from dwarf banana peel has been synthesized successfully using the one-step hydrothermal method. The discarded banana peel was reused as a carbon source for the formation of heteroatom-doped porous carbon. This biowaste-derived
heteroatom-doped porous carbonaceous material (BH-PCM) has plenty of interconnected pores with an acceptable surface area of 213 m2 g1 . Thoroughly characterized BH-PCM has been used as electrode material for supercapacitor using a three-electrode system with an aqueous 1 M H2SO4 solution. The as-
synthesized BH-PCM holds an excellent specific capacitance of 137 F g1 at 0.5 A g1 and an impressive rate performance with a capacitance enduring 51 F g1 at 5.0 A g1 . After 10,000 galvanostatic charge– discharge cycles, an initial capacitance of 94% was maintained. To show the practical applicability of the BH-PCM, the symmetrical two-electrode cell was fabricated and delivered the gravimetric specific
capacitances of 87 F g1 at 1 A g1 . The excellent electrochemical performance of BH-PCM towards
supercapacitor was due to their high surface area, reasonable heteroatom doping rate, and a suitable
degree of graphitization. This study offers a green approach for the development of environmental- friendly potential carbon-based electrode, by converting biowaste to clean/green energy.