Enhanced electrochemical performance of carbon materials derived from wood pitch via green ball-milling

Wood pitch, a byproduct of bamboo and wood production, is a promising raw material for carbon substances because of its high carbon yield and aromatic structures. In this study, a green, solvent-free ball-milling method was employed to control the degree of oxidation of wood pitch by adjusting the milling time. The degree of oxidation degree was positively correlated with the milling time, reaching 0.4 (O/C atomic ratio) at 11 h. The ball-milling process reduced the particle size and enhanced the exposure of the oxygen-containing groups, thereby improving the reactivity. Prolonging the milling time increased the number of oxygen-containing functional groups in wood pitch, improving the electrochemical performance of porous carbon materials. After 9 h of ball-milling, the resulting carbon material exhibited a specific capacitance of 297 F/g at a current density of 1 A/g. It demonstrates advantages such as environmental friendliness, low cost, and easy functionalization, making it a highly promising electrode material for supercapacitors.