Novel macaroni‐sponge‐like pore structure biomass (Zingiber officinale Rosc. leaves)‐based electrode material for excellent energy gravimetric supercapacitor

Abstract

AbstractBACKGROUNDBiomass‐based porous carbon as the basic component of electrodes has received wide interest as a renewable energy storage device with high chemical–physical stability and environmental friendliness. Therefore, novel biomass waste based on Zingiber officinale Rosc./red ginger leaves was synthesized as an electrode‐based carbon material with an abundance of unique macaroni‐sponge‐like hierarchical pore structure, as well as good chemical, physical and economic performance. Template/metal–organic framework‐free red ginger leaf‐based hierarchical porous carbon (RGPC) was prepared using a facile and zero‐residue technique as electrode material for supercapacitor application.RESULTSAdditionally, ZnCl2 impregnation with concentrations of 0.1, 0.3 and 0.5 mol L−1 was utilized for increasing the active sites between electrode and electrolyte ions through interconnecting microchannels. The combination of macaroni‐sponge‐like structure, amorphous nature, optimum specific surface area and availability of oxygen functional groups as a self‐doping heteroatom of RGPC‐0.3 greatly optimized the electrochemical performance of symmetric supercapacitor cells. The RGPC‐0.3 electrode had an ideal specific capacitance of 215.76 F g−1 with a specific energy of 29.966 Wh kg−1 and maximum specific power of 108 W kg−1 at 1 mV s−1 in a symmetric supercapacitor system. Furthermore, a relatively good coulombic efficiency of 71.01% was obtained with a low equivalent series resistance of 0.098 Ω.CONCLUSIONSThis study provides insight into the generation of unique hierarchical porous carbon as a basic component of electrodes for energy storage applications with high electrochemical performance through the utilization of waste red ginger biomass with a simple, facile and cost‐effective strategy. © 2022 Society of Chemical Industry (SCI).