Self-propagating High-temperature Synthesis Of Functionalized Carbon Nanomaterials And Their Properties

Due to the superior mechanical,electrical and chemical properties,carbon nanomaterials have shown great potential in biomedical,environmental and energy fields.Especially for graphene and porous carbon nanomaterials with high specific surface area and high electrical conductivity.In this thesis,two kinds of functionalized carbon nanomaterials were designed and synthesized by using graphite and fructose as the main raw materials,and their properties were studied.Including the preparation of water-insoluble graphene and the study of its conductivity;the preparation of Fe/N co-doped carbon nanoboxes and the study of its ORR catalytic performance.Some meaningful resultsachieved are as followed:(1)GO was prepared by modified Hummers method,and GOGA was chemically modified with different amounts of gallic acid.Eventually,an eco-friendly and simple process SHS technique was developed to reduce GO and GOGA to prepare graphene.XRD,FI-IR,XPS,Raman,TEM and HRTEM were used to characterize its structure characteristics,Zeta potential,contact angle and conductivity test were used to characterize itswater solubility and conductivity.These stucdies found that due to the"repair" effect of gallic acid,the graphene not only improved conductivity(88900 S/m),but also to a certain degree of water-soluble.(2)We synthesized porous and highly graphitic carbon nanoboxes(CNBs)from fructose by SHS process.The conductivity of the obtained CNBs is as high as 40700 S/m,which is higher than that of the reported graphene materials.Then N-doped graphitic carbon nanoboxes supported Fe-based nanoparticles(Fe-N-CNBs)catalyst was finally prepared by calcining CNBs impregnated with FcCl3 solution under NH3 atmosphere,XRD characterization found that Fe-based nanoparticles is composed of Fe,Fe3C and Fe2N nanocrystals.The onset potential(1.03 V vs.RHE)and half-wave potential(0.875 V vs.RHE)of the Fe-N-CNBs-600 catalyst is 20 mV and 30 mV more positive than those of the commercial Pt/C,respectively.The catalyst also outperforms Pt in the stability and methanol tolerance in alkaline.