Improved Electrocatalytic Performance From Graphene Quantum Dots/Three-Dimensional Graphene/Polyaniline Doped Powder To Layer-By-Layer Self-Assembled Membrane Materials

In this paper, three-dimensional network graphene and graphene quantum dots were prepared using graphite powder as the initial raw material. After that, the method of self-assembly of graphene quantum dots (GQDs) on the surface of three-dimensional graphene (3D-G) was used to prepare GQDs/3D-G composite to solve the problem of easy agglomeration of graphene in the process of composite preparation, and then it was mixed with polyaniline (PANI) aqueous solution in different contents to form graphene quantum dots/three-dimensional graphene/polyaniline (GQDs/3D-G/PANI) doped composite. The obtained GQDs/3D-G/PANI doped materials exhibited a specific morphology of nanoscale polyaniline firmly attached to the 3D networked graphene layer, which was attributed to the good dispersion of 3D network graphene and polyaniline in water. Graphene quantum dots facilitated close contact between the three-dimensional graphene sheet and the polyaniline particles, which significantly reduced agglomeration. In addition, driven by the strong electrostatic force between the positively charged polyaniline and the negatively charged GQDs/3D-G and the pi-pi interaction, the nanoscale GQDs/3D-G/PANI thin film layer was obtained by layer-by-layer self-assembly on the hydroxylated ITO plate, which showed the morphology of an interconnected layer network and exhibited good electrochemical catalytic activity for H2O2.