Porous activated carbon derived from petroleum coke as a high-performance anodic electrode material for supercapacitors

Abstract

In recent times, there has been a significant demand for supercapacitors in energy storage applications due to their rapid charging–discharging capabilities, high power density, and excellent stability. Nevertheless, the synthesis of electrode materials with a substantial surface area, exceptionally high porosity, and superior electrochemical performance is still challenging. Activated carbons with a distinctive porous structure and exceptional electrochemical properties emerged as promising electrode materials for supercapacitors. In this study, we used a porous activated carbon (PAC) derived from petroleum coke followed by KOH activation as an efficient anodic electrode material. The ultra-high Brunauer–Emmett–Teller surface area of 2105.6 m² g⁻¹ with stacked layers of carbon atoms arranged in a two-dimensional hexagonal structure makes the PAC an efficient candidate for a supercapacitor electrode. The PAC delivers a specific capacitance of 470 F g⁻¹ at a current density of 0.5 A g⁻¹ over a potential window of 0 to −1 V. The excellent cycling stability in a three-electrode setup with a capacitance retention of ⁓98% even at a high current density of 10 A g⁻¹ makes the PAC a potential anodic electrode material for high-performance supercapacitor applications.

Graphical abstract

Petroleum coke-derived highly porous KOH-activated carbon providing an ultra-stable supercapacitor performance