Heteroatoms doped porous carbon derived from waste potato peel for supercapacitors

In terms of supercapacitor electrode materials, biomass derived carbon electrodes are gaining much attention as a viable option for practical applications. Obtaining unique carbon nanostructures can significantly promote the electrochemical performance. Waste potato peel (WPP) derived hierarchical porous carbon materials with heteroatoms doping can boost the development of efficient and economical electrodes with improved charge storage capabilities. Here, we report sulfur and phosphorus co-doped porous activated carbon (S, P/PAC) as an effective supercapacitor electrode material with a large specific surface area. More importantly, the S, P/PAC not only acquires dual heteroatoms doping for promoting capacitive performance but also possesses fascinating porous features which are beneficial to shorten ion adsorption distances and enlarge the contact area. The electrode exhibits a high specific capacitance of 323 F g−1 at 1 A g−1, acceptable rate capability and good cycling stability after 5000 cycles. The constructed symmetric supercapacitor device with a wide operational potential window of 1.6 V achieves a maximum energy density of 45.5 Wh kg−1 at a power density of 800 W kg−1 with an improved long cycle life (94.3 retention after 10 000 consecutive cycles).