Synthesis And Application Of Hierarchical Nitrogen-doped Carbon Composites Derived From Polyaniline

Carbon nanomaterials are widely used in various fields, such as electrochemistry, catalysis, sensing and adsorption, because of their controllable morphology and excellent properties. It is proved that the properties can be improved by modifying the carbon nanomaterials, such as activation, doping, and composite. Hetero atoms (N, B and S) can effectively control the crystal structure and electronic structure of carbon nanomaterials, resulting in the excellent physical and chemical properties. N is an ideal element for the doping of carbon nanomaterials, which can effectively improve the properties of mechanics, electrochemistry, catalysis and adsorption. Pyrolysis of polymers is one of the effective methods for the preparation of N-doped carbon nanomaterials. PANI has become an ideal N source because of its controllable morphology and low cost.In this paper, the materials with novel structure and excellent properties were prepared by using the hierarchical N-doped carbon nanomaterials derived from PANI. Specific work is as follows:(1) N-doped hierarchical porous carbon nanowhisker ensembles on carbon nanofiber for high-performance supercapacitorsN-doped carbon nanomaterials with special structure were synthesized by hydrothermal polymerization and high temperature pyrolysis. The experimental operation is simple and convenient. And the structure of one-dimensional hierarchical core-shell is novel. The pore structure, specific surface area, content of nitrogen element can be controlled by changing the annealing temperature. The electrochemical test results show that, NHCNs-750 after pyrolysis at 750 ? has excellent electrochemical properties. In this work, the N-doped method is simple and easy to operate, the source of N (PANI) is cheap and easy to get, the structure of one-dimensional hierarchical core-shell is novel, and the electrochemical performance is excellent, which all make a certain contribution for fabrication of novel electrochemical materials.(2) N-doped carbon nanoplates for the efficient electrochemical determination of AA, DA, and UAAscorbic acid (AA), Dopamine (DA), and uric acid (UA) are very important neurotransmitters in the human body, and their oxidation peak potentials are very close. Therefore, it is very important for human health to detect AA, DA and UA in an efficient way. We have combined the hierarchical structure of N-doped carbon and NiCo nanoparticles to prepare the N-doped carbon/NiCo nanoparticles (NiCo-NPs-in-N/C) with sandwich structure. The formation mechanism of the material can be investigated by changing the annealing temperature. As a result, such an intriguing structure shows superior catalytic activity towards the electrooxidation of AA, DA, and UA. The composite can synthesize the catalytic activity of N-doped carbon nanoplates and NiCo nanoparticles to improve the selectivity and sensitivity. The carbon layer outside can protect NiCo nanoparticles from corrosion and aggregation, which can improve the stability and reproducibility of materials. This work provides a new direction in the field of biosensors.