Synthesis and electrochemical evaluation of porous carbon derived from sanitary pad waste for high performance in symmetric supercapacitor application

In recent years, the renewable energy storage system has attracted considerable attention from both industry and academia to address the ongoing global climate change. The waste derived porous materials gained attention as excellent electrode materials due to large specific area, good electrical conductivity to enhance ion transport and charge transfer. In this study, waste sanitary pad biomass has been successfully converted into carbon material through one-step simultaneous carbonization and activation by KOH. The as-prepared activated carbon at various temperatures was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray spectroscopy (XRD), scanning electron microscopy (SEM), Raman spectroscopy and Brunauer-Emmett-Teller (BET) techniques. The prepared biomass derived activated carbon (SWAC 800) electrode, with a large surface area of 396.1 m²g⁻¹ delivered high specific capacitance of 306 Fg⁻¹ at 1 Ag⁻¹ with excellent cyclic stability in a 6 M KOH aqueous electrolyte. The electrochemical performance of the SWAC 800 electrode in a symmetric supercapacitor was evaluated in 6 M KOH and 1 M Na₂SO₄ electrolytes. The neutral Na₂SO₄ electrolyte assist SWAC 800 symmetric supercapacitor device produce excellent energy density of 32.7 Wh.kg⁻¹ in 1.6 V operating potential window. Overall the SWAC from renewable biowaste is prospective candidate for high performance electrode material for supercapacitor application.