Preparation Of Porous Graphene By Carbide Reduction Etching

Porous graphene (PG), a derivative of graphene with nano-scale pores on the sheets, has exhibited some distinct physical and chemical features. The pores on the graphene sheets may contribute to the improved mass and electron transfer, which may find many potential applications. To date, the preparation of porous graphene includes physical preparation by high-energy techniques and template methods (template growth and template etching). However, these methods are generally conducted on substrates with limited yields, hampering their further practical application.Tn this thesis, we develop a general and scalable synthetic method for porous graphene via carbothermal reduction reaction using monodisperse zinc oxide nanoparticles. The results indicate that as-prepared ZnO nanoparticles are first attached on graphene oxide nanosheets by electrostatic interaction and then undergo a carbothermal reduction reaction at 800℃ to produces the pores on the sheets, while graphene oxide nanosheets are thermally reduced to graphene simultaneously. All by-products (carbon monoxide, carbon dioxide and zinc) during this process are in the gaseous state at high reaction temperature and can be escaped from the final products. The characterizations of the obtained porous graphene reveal that the pore size is about 11 nm, larger than that of ZnO nanoparticles (-5 nm), which is ascribed to the aggregation of ZnO nanoparticles (-20 nm) on the graphene oxide sheets. These results show the certain correlation among the sizes of pores, ZnO nanoparticles and ZnO aggregations, which gain insight into the controlling of pore size by choosing suitable etching agent.In summary, by using carbothermal reduction etching method, we successfully realize the inexpensive and large-scale synthesis of porous graphene, of which the production can reach gram level. This work paves the way for the practical applications of porous graphene in the future.