| Environmental pollution and energy crisis are the two big challenges of the sustainable development of modern human society, the main reason is the use of fossil fuels, which could cause serious environmental pollution and energy draining. Among various technologies in response to the challenge, semiconductor photocatalysis and energy storage have become one of the most promising technology. On the one hand, it can use abundant sunlight energy to degradate pollutants effectively, on the other hand it can reach energy storage and reduce the use of fossil fuels.Recently, graphite carbon nitride(g-C3N4), as a kind of catalyst without the metal, attracted widespread attention because of its narrow band gap(2.7 eV),which can absorb visible light directly, the unique properties make g-C3N4 ap ply in organic synthesis, pollution treatment, photocatalytically splitting of water into hydrogen and energy conversion. However, g-C3N4 electronic-hole recomb ination rate is high, which makes photocatalytic activity low, so the modificatio n is one of our main research direction.In addition, carbon material is widely used as super capacitor’s electrode ma terial, but its low specific capacity limits its practical applications, as a simple nitrogen-doped carbon material, the performance of graphite carbon nitride in super capacitor is worth anticipated.In view of the above problems, this paper use the method of cerium-doped carbon nitride and grapheme-nitride carbon nanocomposites to improve the photocatalytic performance of carbon nitride and study the performance as super capacitor electrode materials.(1) With cerium nitrate and melamine as raw materials, the cerium-doped carbon nitride is prepared by the way of simple mechanical mixture, and their structure characterization were analysised by XRD, TEM and FTIR, the results show that using the simple mechanical mixture method can successfully prepared cerium-doped carbon nitride and dispersed evenly, doped cerium exists in the form of cerium oxide and the size of cerium oxide particle is around 8 nm.(2) With methylene blue and methyl orange as the degradation dye, the effect of different proportion of doped cerium on the photocatalytic properties of carbon nitride is studied, the results show that doped cerium effectively improve the photocatalytic properties of carbon nitride, the photocatalytic performance of Ce(1.5%)-C3N4 sample is the best, after the light radiation for 25 min and 100 min, the degradation rate of methylene blue and methyl orange are 98.1% and 93.1%, respectively.(3) Graphene oxide were synthesised using Hummers method, then with citric acid as reducing agent, reduced the graphene oxide and prepared grapheme-nitride carbon nanocomposites by one-step hydrothermal method, the characteristic of graphene-nitride carbon nanocomposites material is analysised through XRD, TEM, FTIR and other characterization methods, the results show that oxidation graphene is reduced well and composite with carbon nitride together, the composite material has layer plate structure.(4) With methyl orange as the degradation dye, the graphite phase of graphene-nitride carbon nanocomposites effects on the photocatalytic properties of the carbon nitride were studie. the results show that the addition of graphene can significantly improve the photocatalytic properties of the nano-composites, among which the photocatalytic performance of GCN-2 samples is the best, after the light radiation for 100 min, the degradation rate of methyl orange is 90.9%.(5) Using three electrode system, electrochemical capacitor performance of graphene-nitride carbon nano-composites was researched by cyclic voltammetry and ac impedance method, our results show that the nano-composites material has good internal charge transfer, and the addition of graphene effectively improve the performance of electrochemical capacitors material. |
PDF Full Text Request