Phosphomolybdic acid embedded into biomass-derived biochar carbon electrode for supercapacitor applications

Abstract

In high-performance, clean, safe, and cost-effective ways, supercapacitors are among the most promising ways to store and release nonfossil energy. In recent years, renewable biomass-derived activated carbon has been explored as a potential option for electrode material. It restricts their specific capacitance despite being environment-friendly and possessing intrinsic mechanical strength. In order to overcome this limitation and preserve all other properties, we are infusing polyoxometalate into the activated carbon; this increases specific capacitance with its fast reversible redox behaviour and preserves the carbon's characteristics. Beside suffusing phosphomolybdic acid (PMA) into biomass waste material, such as orange peel-derived activated carbon (OPAC), a new hybrid material (OPAC-PMA) was developed. The nanohybrid design was revealed by structural and morphological research, which showed high interfacial contact, allowing polyanions to redox rapidly. The novel hybrid electrode material (OPAC-PMA) has a capacitance value of 66% higher than the bare OPAC electrode. A further study showed that OPAC-PMA composite showed 88.23% cycle stability in 0.5 M H<inf>2</inf>SO<inf>4</inf> electrolyte at 6 A g−1 for 4000 cycles. © 2023 Elsevier B.V.