The invention discloses a
covalent modification method of a high-performance
lignin-based
electrode material, and belongs to the technical field of
biomass-based supercapacitors. The method specifically comprises the following steps: dissolving
sulfate lignin in DMF (
Dimethyl Formamide), adding a
bifunctional reagent, and stirring for reaction; and after the reaction is finished, pouring the reaction liquid into deionized water in which
hydrochloric acid is dropwise added, and carrying out anti-
precipitation,
filtration,
drying, heat treatment, activation and other processes to obtain the covalent modified
lignin. The modified lignin, a conductive agent and a binder are ground and mixed, a
current collector is coated with the mixture and dried, and the lignin-based
electrode is obtained. The
covalent modification degree of the lignin is regulated and controlled by controlling the adding amount of the
bifunctional reagent, modified lignin with different thermodynamic properties is obtained, and the purpose of regulating and controlling lignin derived carbon structure defects is achieved. The preparation method is controllable in scale and simple to operate, the obtained
electrode material is few in defect structure and excellent in electrochemical performance, and a new theory and a new method are provided for development of the lignin-based
electrode material.