Effects of tree species pore structure characteristics and CO2 activation on the performance of their derived carbon electrode for supercapacitors

Herein, we investigated the effects of tree species selection on the specific surface area and electrochemical properties of wood-derived carbon electrodes. The SEM, Raman spectra and aperture distribution test results showed that compared with BCW and ZCW, CW had a more complex hierarchical porous structure and more defects. The N₂ adsorption/desorption isotherms and electrochemical test results showed that CW had the largest specific surface area and the best electrochemical performance, with a specific surface area of 495.3 m² g⁻¹ and an areal capacitance of 3079 mF cm⁻² at 5 mA cm⁻². The specific surface area and electrochemical properties of ACW, ABCW and AZCW electrodes obtained by CO₂ activation were significantly improved compared with CW, BCW and ZCW electrodes. Among the activated electrodes, the ACW electrode had the highest specific surface area (558.4 m² g⁻¹) and the highest areal capacitance (3727 mF cm⁻² at 5 mA cm⁻²).