Preparation And Electrochemical Properties Of Nitrogen-doped Porous Carbon Materials

More and more researchers have been attracted by Nitrogen-doped porous carbon for its advantages of high specific surface area, suitable porous structure, nitrogen-doping and so on.Nitrogen-doped porous carbon has shown a potential application prospect in the area of catalysis and supercapacitor as an ideal material of electrode. This article used different methods and processes to prepare Nitrogen-doped porous carbon, which was applied in catalysis and supercapacitor in further experiments. And we also discussed the catalytic performance and capacitive performance of those carbonmaterials.Nitrogen-doped porous carbons(NPC-700, NPC-800, NPC-850, NPC-900) were prepared at different carbonization temperature(700-900℃) by hard-templating method with melamine and formaldehyde. The influences of nitrogen amount and nitrogen-containing groups on the electrochemical performance were researched when NPCs were applied in catalysis and supercapacitor. The results show that, with the increasing of carbonization temperature, the specific surface area and the volume of porous increase, while the content of nitrogen decrease. Among that the content of N-6 and N-5 have increased and the content of N-Q has decreased. NPC-800 has high specific surface area, suitable porous structure and appropriate ratio of nitrogen functional groups. So,in catalysis, NPC-800 has small charge transfer resistance of 1.5 Ω and high peak current density and shows better catalytic performance than Pt. In supercapacitor, the specific capacitance of NPC-800canreachupto168 F g-1 andkeeptherateratioof95%by thetestof10000 cycles.Nitrogen-doped porous carbons of NMC and NHPC were prepared by soft-templating method with melamine and formaldehyde. The effect of porous structure and nitrogen element on catalytic performance and capacitive performance were studied when NMC and NHPC were used in catalysis and supercapacitor. The results show that, there are two influence factors, one is porous structure and specific surface area, the other is the doped-nitrogen element. NHPC has high specific surface area,micro-meso porous structure and nitrogen content of 1.5%, shows good performance of catalysis and capacitance. The specific capacitance of NHPC can reach 258 F g-1and keep the rate ratio of 97.5%after5000cyclesofgalvanostatic charge/discharge.Nitrogen-doped nano-graphites were prepared by magnetic stirring grinding method with the325 mesh graphite under ammonia atmosphere by differnent grinding times from 0~10 h. SEM,XRD and XPS were carried out to characterize the prepared materials. The results show that, the specific surface area and the degree of graphitization no longer change when the grinding time over 5hours. The researches show that, NNG-5 presents better catalytic performance than Pt with the synergistic effect of suitable porous size distribution and nitrogen-doping. NNG-5 also shows goodcapacitive performancewith thespecific capacitance of 190 F g-1and keeps thecapacitive rate of53%atthefrequencyof6 Hz.