Synthesis of porous carbons from coal tar pitch for high-performance supercapacitors

Publication date: April 2019Source: New Carbon Materials, Volume 34, Issue 2Author(s): Feng Wei, Han-fang Zhang, Xiao-jun He, Hao Ma, Shi-an Dong, Xiao-yu XieAbstractPorous carbons (PCs) for supercapacitors were synthesized by a combined Mg(OH)2 templating and in-situ KOH activation method using coal tar pitch as the carbon precursor, and were characterized by TEM, Raman spectroscopy, XPS and N2 adsorption. Their electrochemical properties were investigated by galvanostatic charge-discharge, electrochemical impedance spectroscopy and cyclic voltammetry. Results show that the specific surface area of the PCs increases with the KOH dosage and exhibits a maximum with an activation temperature at 800 °C. The optimum PC has a high surface area up to 3 145 m2 g−1 with abundant micropores, and exhibits a high specific capacitance of 272 F·g−1 at 0.05 A·g−1, a rate capability of 217 F·g−1 at 20 A·g−1 and a good cycle stability with a 96.69% capacitance retention after 10000 cycles in a 6 mol/L KOH electrolyte. This work provides a simple method for the large-scale production of PCs from pitch-based carbon sources for high-performance supercapacitors.

Source: New Carbon Materials - July 12, 2019 Category: Chemistry Source Type: research