The Synthesis Of Nitrogen-doped Porous Carbons Based On P-nitroaniline And Phenidone A And The Reaserch Of Their Properties For Supercapacitor

As a new energy storage device which bridges the gap between capacitor and battery, supercapacitor has attracted increasing attention of researchers because of its short charging time, wide working temperature range and excellent recycling ability. For a supercapacitor, the selection of its electrode materials is crucial. Carbon materials has been increasingly used as electrode materials of supercapacitor for its excellent features, such as high specific surface area, good heat/electric conduction, and low manufacture cost. This dissertation mainly focuses on using simple and effective ways to synthetize heteroatom-doped carbon materials which is suitable for applying in supercapacitors. The specific content is as follows:1. Nanoporous carbon materials co-doped with both nitrogen and sulfur have been synthesized via a sulfuric acid-assisted straightforward carbonization method, in which 4-nitrobenzenamine serves as both carbon and nitrogen source, whereas sulfuric acid as sulfur source and catalyst. It is revealed that the nanoporous carbon material named as carbon-RT takes on amorphous features with low crystallinity. More importantly, it possesses high nitrogen content （15.95%） and sulfur content （3.36%） in matrix. To improve the electrochemical performance of material, the carbon-RT sample was further heated in a horizontal tube furnace up to 800℃ for 2 h. As a result, a high specific capacitance of 73 F g^-1 is delivered at the current density of 1 A g^-1 when measured in a three-electrode system, using 6 mol L^-1 KOH as electrolyte. The present synthesis method has been conveniently implemented to produce nanoporous carbon materials co-doped with high content of nitrogen and sulfur within a very short time, thereby it has broad prospects and potentials for producing carbon materials in a simple and scalable manner.2. In this study, we present a simple but efficient template carbonization method to prepare nitrogen-doped nanoporous carbon material, in which phenidone acts as carbon/nitrogen sources and Mg（OH）₂ as hard template. The results indicate that the carbon-1:1 sample is highly disordered with large BET surface area of 1513 m² g^-1, high pore volume of 2.2 cm3 g^-1 and nitrogen content of 3.78%. As a result, it exhibits decent electrochemical behaviors, whose specific capacitance reaches up to 202.0 F g^-1 when measured at 1 A g^-1 in a three-electrode system. Moreover, azodicarbonamide has been introduced in the process of carbonization to further tailor the porosity of nanoporous carbon, named as the carbon-1:1:1 sample. In consequence, its BET surface area has decreased to be 1261 m² g^-1 but the pore volume increased up to 2.8 cm3 g^-1, together with the large enhancement of nitrogen content up to 7.05%. Besides, it thus delivers a higher specific capacitance of 281.0 F g^-1 at 1 A g^-1, mostly due to the incremental content of nitrogen species. The proposed Mg（OH）₂-assisted template carbonization method has provided an intriguing synthesis approach for N-doped nanoporous carbons, especially the nitrogen improvement simply by the addition of azodicarbonamide.