Synthesis and Application of Conductive Pitch‐Based Porous Carbon for Energy Storage Device as a Supercapacitor

ABSTRACT Conductive pitch‐based porous carbon materials were synthesized and systematically investigated as high‐performance electrode materials for supercapacitors. Petroleum‐derived pitch was thermally treated and chemically activated using KOH and NaOH at different pitch: activating agent molar ratio (1:1, 1:2, and 1:4) to optimize the pore structure and electrical conductivity. The resulting activated carbons exhibited large specific surface areas (up to 1686 m 2 g −1 ) and high micropore fractions (84–90%). Among them, the KOH‐activated sample prepared at a 1:2 ratio displayed the highest specific capacitance of 112.6 F g −1 at 10 mV s −1 in a three‐electrode system using an Ag/AgCl reference electrode. Electrochemical impedance spectroscopy revealed that the NaOH‐activated sample at a 1:4 ratio showed the lowest charge‐transfer resistance (2.7 Ω) due to its superior conductivity (51 S cm −1 ), whereas the KOH‐activated 1:2 sample exhibited enhanced ion diffusion attributed to its high micropore fraction. These results indicate that micropore fraction and conductivity, rather than total surface area alone, predominantly govern the electrochemical behavior of pitch‐derived carbon electrodes. This study demonstrates that pitch‐based porous carbon is a cost‐effective and structurally tunable material platform for next‐generation energy storage devices.