Fabrication of resorcinol-based porous resin carbon material and its application in aqueous symmetric supercapacitors

Abstract

Carbon materials with porous structures with their unique surface area and charge transport properties have been attracting significant attention as electrode materials in renewable energy storage devices. The rapid agglomeration of layered materials during electrochemical processes reduces their shelf life and specific capacitance, which can be prevented by the introduction of suitable pores between the layers. In this study, resorcinol-based porous resin carbon was facilely prepared via a simple carbonization of the potassium salts of resorcinol-potassium resin. The morphology, structure and surface properties of the carbon materials were investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), N₂ adsorption and energy dispersive spectroscopy (EDS). It is proposed that the fast nucleophilic addition between the phenols and formaldehyde produces nano-sized gel particles, followed by carbonization into carbon particles, finally packing to the mesopores. Due to the synergistic effects of the tailored porosity and O-doping, the prepared carbon materials show a high specific capacitance (198 F g⁻¹ for RC700), good capacitance retention (96.5% for RC700) at 2 A g⁻¹ in 6 M KOH and the specific area of RC700 is 540 m² g⁻¹.