Preparation of N-doped Polypyrrole-derived Porous Carbon and Its Electrochemical Properties

Hyper-crosslinked polymers are inexpensive materials that have a high carbon content, making them ideal carbon precursor. In this study, hyper-crosslinked PPy was prepared by a solvothermal method. Using it as a precursor, N-doped porous carbon (PPyCN-800-B) was prepared by using urea, and the effects of the N doping ratio on the microstructure, components, and electrochemical properties of PPyCN-800-B were studied. The results demonstrated that PPyCN-800-1:4 was formed by the accumulation of non-hollow nanospheres of different diameters. The N content increased from 3.89% of PPyC-800 to 8.08%. When the current density was 1 A g(-1), the specific capacitance of PPyCN-800-1:4 increased from 109.1 F g(-1) for PPyC-800 to 228.0 F g(-1), and the current density was increased from 1 A g(-1) to 10 A g(-1), with a specific capacitance decay rate of 16.67% in 1 M H2SO4 electrolyte. After 5000 charging/discharging cycles, the capacitance retention was as high as 89.53%, showing the good cyclic stability and excellent electrochemical properties of PPyCN-800-B. N doping increased the number of porous carbon defects, produced more active sites with pseudocapacitance, and improved the material's wettability. This, in turn, facilitated the adsorption and desorption of electrolytic ions and significantly improved the electrochemical properties of porous carbon.