Sustainable synthesis of heteroatom-doped porous carbon skeleton from Acacia auriculiformis bark for high-performance symmetric supercapacitor device

Abstract

In recent years, the applications of biomass-derived meso/microporous carbon materials have fascinated increasing research attention due to their cost-effective and easy synthesis pathways. Researchers are using different types of biological precursors such as bark, leaves, roots, peels, fruits, and biological waste, etc., to synthesize porous carbon materials. In energy storage applications, the biomass-derived activated porous carbon may achieve an excellent capacitance, durability, and rate capability, compared to artificial nanomaterials, such as carbon nanotubes, fullerene, graphene, etc., due to their intrinsic and hierarchical structure. A clear understanding of the elemental and chemical composition, and porous nature of the biological precursor may be required to obtain a high-carbon yield, graphitized, high-energy, and power density carbon materials. In this work, novel heteroatom doped, and interconnected nanoflake-like porous carbon materials have been synthesized from Acacia auriculiformis bark for high-performance energy-density storage applications. The existence of the heteroatom in the carbon framework enhances the pseudocapacitive property of the materials. The synthesized porous carbon demonstrates the maximum specific capacitance 324 F g−1 and 288 F g−1 at 1 A g−1 current-density in acidic and neutral electrolytes, respectively. The electrokinetic analysis of the synthesized porous carbon materials demonstrates the maximum capacitive contribution to overall charge storage using both electrolytes. The fabricated solid-state symmetric device has a maximum capacitance of 107 F g−1 along with an energy density of 59.44 Wh kg−1 and power density of 10 kW kg−1. The synthesized heteroatom-doped porous carbon (H-PC) materials display outstanding durability up to 10,000 continuous cycles using a solid-state device even in strongly acidic conditions.