Synthesis of flake-shaped nitrogen-doped carbon quantum dot/polyaniline (N-CQD/PANI) nanocomposites via rapid-mixing polymerization and their application as electrode materials in supercapacitors

Flake-shaped nitrogen-doped carbon quantum dot/polyaniline (N-CQD/PANI) nanocomposites were prepared as electrode materials in supercapacitors via rapid-mixing chemical oxidative polymerization of aniline in the presence of the nitrogen-doped carbon quantum dots (N-CQDs) containing abundant amino groups, which were synthesized via a one-step microwave pyrolysis with citric acid (CA) as the carbon source and 1,2-ethylenediamine (EDA) as the surface passivation agent. The effect of the synthetic conditions on the morphology, electrical conductivity and electrochemical properties of the resultant nanocomposites was investigated. The electrochemical experiments showed that all the N-CQD/PANI nanocomposites exhibited higher specific capacitances than the PANI one, and the N-CQD/PANI-3 one, prepared at an aniline concentration of 0.02 mol/L with a feeding ratio of N-CQDs to aniline of 10 wt%, possessed the highest electrical conductivity, specific capacitance, rate capability and cycling stability.