Preparation And Properties Of Graphene-Ag Composite Paper

Chemical reduced graphene (CRG) has attracted many researchers, for it has many superlative properties and is easy to prepare. In this paper I use Hummers method to prepare graphite oxide and use three different methods to reduce it. Based on the CRG, I have studied the preparation and properties of graphite oxide paper, graphene paper and graphene-Ag composite paper. As follows:I demonstrated that the individual graphene oxide sheets can be readily reduced by using phenolphthalin as both reducing agent and stabilizer. Phenolphthalin can reduce graphene oxide in DMF and anchor on the surface of graphene via π-π stacking as well, the obtained graphene can be dispersed in organic solvents easily, which can give potential applications in large scale production of oil dispersible graphene and facilitate the preparation of polymer-graphene nanocomposites.A facile route for the large scale production of graphene oxide (GO) papers and their mechanical enhancement has been presented in this work. The novel paper-like GO made from individual GO sheets in aqueous suspension can be achieved in large scale by a simple drop casting method on hydrophobic substrates. Significant enhancement in mechanical stiffness (341%) and fracture strength (234%) of GO paper have been achieved upon modification with a small amount (less than10wt%) of glutaraldehyde (GA).By using ascorbic acid as a reducing agent, the graphite oxide films dipped in Ag+aqueous solutions can be easily reduced, accompany with the decoration of uniformly distributed Ag particles. And it reveals that the resultant films exhibit excellent mechanical and electrical properties. With the tensile strengths and Young’s Modulus as high as68MPa and7.3GPa the sheet resistance at about500Ω/□.Those graphene oxide paper or composite films hold a great potential for applications in various fields such as supercapacitor, electrode materials, and catalysis.