Design,Synthesis And Property Study Of Carbon Based Inorganic Nanomaterials

Carbon as one of the few elements that have been found in ancient times, owns highthermal stability and is hard to be etched. It is highly conductive after heat treatment andcan bind with metal elements to form hybrid structures with synergetic effects. Theresulting material usually shows outstanding catalytic properties in energy field and hasdrawn great attention among researchers. The star material Graphene that won an NobelPrize exhibited unique charm of carbon material in a different way. It owns large specificsurface area, high conductivity, great mechanic property and lightweight, at the same timeis very easy to synthesis. The oxidized form of it: Graphene Oxide in strong acid evenoffers better platform for it to combine with metal or metal oxide nanoparticles.Almost all material has a new look and functions better after combining with graphene,which attracts a huge market. Besides, people have found that the doping of nitrogen, boron,fluorine or phosphor in graphene could further change and enhance its electronic structureand increase its properties in electro catalysis and other areas. The focus of this work is tostudy the remolding and the decoration of carbon materials, combining them withmetal/metal oxide nanoparticles, achieving better performance in multi-fields and analyzingthe mechanisms. By far the resulting products have shown great performance in microwaveabsorption, propellant decomposition catalysis, lithium ion batteries and oxygen reductionreactions, enjoying significant prospect in industrialization.In this work we designed and successfully synthesized a series of carbon basedmaterials using microwave-assisted method, hydrothermal method and wet chemistrymethod. Ni, Co, CoNi, Mn3O4, Cu2O nanoparticles anchored or wrapped tightly on carbonbase, showed obviously enhanced properties in various fields with lower cost.1. With Vc as carbon source, Ni-C and CoNi-C are synthesized at120oC withsolvothermal method. The material is used in radar absorption and is characterizedthoroughly. The metal nanoparticles with an average diameter of10nm dispersed evenly oncarbon base and is strongly against etching with makes it super stable in extreme conditions.The method is also easy and repeatable with high yield. After comparison it is found that Ni-C-18.2%can reach35dB for reflection loss at the thickness of4mm with a wideabsorption peak that is better than most absorbers of radar. Another product CoNi-Cachieved reflection loss more than10dB in the whole range of5-18GHz. The bestabsorption of50.2dB appeared at7.7GHz at the thickness of4mm. This product designoffers new strategy for microwave absorber synthesis because of its low cost, high yieldand other advantages like light weight and environment friendly.2. Mn3O4/GS and Ni/GS are synthesized for the thermal decomposition of ammoniaperchlorate (AP). They are easily synthesized by one pot approach through which grapheneoxide is reduced to graphene completely. The metal ions interact with functional groups ongraphene oxide and become nanoparticles with uniform size and morphology. The productsown big specific surface area and high conductivity. No agglomeration is observed sincegraphene sheets are inserted in between the particles, providing more efficient active sitesfor catalytic reactions. The final decomposition temperature of AP is tested to decreaseabout100℃after adding the as synthesized products. The outstanding results may lead toinspirations of many other new composite designs used in AP decomposition.3. Cu2O@Cu-GS is designed as electrolyte in lithium batteries with bi-conductingsystem and is synthesized by microwave-assisted method. Cu2O@Cu has a core-shellstructure and dispersed on the surface of graphene averagely with a uniform diameteraround100nm. Its capacity reaches775mAh/g at the current density of50mA/g, far morethan Cu2O@Cu （less than100mAh/g） and Cu2O-GS （416mAh/g）. Variouscharacterizations show that graphene plays an important role in increasing the stability andcapacity of the composites and the Cu layer also helps conduct electrons faster to improvethe final performance. This design can lead to the synthesis of materials with similarstructures like NiO@Ni-GS, Fe3O4@Fe-GS and Co3O4@Co-GS used in lithium batteries.4. A facile method is designed for the production of nitrogen doped nano carbonshells with high yield. The product shows outstanding electrocatalytic properties in oxygenreduction reactions and achieved reaction potential of-0.229V. It can be used inelectrolytes of fuel cells in the future and performs better than commercial platinum/carbonmaterial (20%) and other nitrogen doped carbon materials. It doesn’t show poisoning effectin methanol and is extremely stable in alkali. Its chemical activity is comparable to nitrogen doped graphene and nanotubes but with a much easier way to synthesis. Thermal treatmentconditions are carefully studied and the best annealing temperature is800℃for propernitrogen doping and best performance, offering reference for the synthesis of similarmaterials.