Astragalus brachycalyx fischer roots-derived porous carbon integrated with a novel NiSnO 2 /PC nanocomposite for high-performance supercapacitors

The NiSnO 2 /biomass-derived porous carbon (PC) composites were synthesized from the roots of Astragalus brachycalyx fischer by using a series of physicochemical processes. Then, the composites were characterized by XRD, SEM, BET, Raman and EDS to illuminate and confirm the structures. The NiSnO 2 /biomass-derived PCs were employed as a new class of renewable supercapacitor electrodes. The electrochemical performance of the prepared PC electrodes was analyzed by using two electrodes in a 6 M potassium hydroxide (KOH) aqueous solution electrolyte. Electrochemical measurements revealed that NiSnO 2 /PC nanocomposites demonstrated highly effective stability with a specific capacitance of 295.90 F/g at 200 mV/s for supercapacitor studies, and a capacitance retention rate of 38.70% after 200 cycles. The high surface area and the presence of large hierarchical pores contributed to the effective electrochemical performance of the prepared nanocomposite materials. The NiSnO 2 /PC nanocomposites with the 3D porous structure have showed that promising efficiency in the application of supercapacitors with its high energy storage capacity and effective electrochemical performance.