Abstract: In order to prepare high-performance and low-cost electrode materials, nickel ion-doped polyANI-coated biomass carbon composite materials (Ni@PANI/BC) were synthesized by chemical oxidation polymerization using August melon peel biomass carbon (BC) as the matrix, and nickel nitrate and aniline as raw materials. The structures of the Ni@PANI/BC composites were characterized by SEM, EDS, X-ray photoelectron energy spectrum (XPS), thermal weight analysis (TG) and specific surface area test (BET), and the electrochemical properties of the composites were measured by cyclic voltammetry (CV), constant current charge and discharge (GCD) test and electrochemical impedance spectroscopy (EIS). The effects of nickel ion doping on the structure and electrochemical properties of Ni@PANI/BC were investigated. It is shown that nickel ion doped BC forms a porous cross-linked mesh porous structure with large specific surface area and good electrical conductivity. When the mass ratio of nickel hydrate nitrate, aniline and BC is 1.5∶5∶3, the obtained electrode material has the best electrochemical performance. At 1 A/g current density, Ni@PANI/BC mass capacitance is up to 608.4 F/g, 5 000 cycles with a capacity retention rate of 85.4%, which demonstrates Ni@PANI/BC materials have electrochemical properties comparable to the relevant materials reported in the literature.

Key words: biomass carbon, polyaniline, chemical oxidation polymerization, composite, capacitance, electrochemical property