Study For The Conditions Of Reduction Of Graphite Oxide

In nature environment, Carbon has many allotropes, for instant sp3hybridizationdiamond, sp2hybridization graphite and acetylene of sp hybridization. Fullerene,carbon nanotube and single-layer graphene were respectively found in1985,1991and2004. The explorations have expanded the category of carbon-material allotropes andinduced the revolution of nanoscience and nanotechnology. Graphene, so-calledsingle-layer graphite, is a novel carbon material and its construction is two-dimensional honeycomb crystal lattice by accumulation of single-layer carbon atoms.As recently demonstrated, graphene can be obtained in bulk quantity by chemicalreduction of graphene oxide in solution. Because of the existence of the vander Waalsnteractions, the as-reduced graphene sheets tend to form irreversible agglomerates andeven return to graphite. Inorder to obtain high-dispersion graphene, The incorporationof some non-organic molecules or polylllers into the sheets is an approach to reducethe aggregation or introduction of some dispersants in the restore process, such asCTAB, Sodium dodecyl benzene sulfonate, polyvinyl alcohol, tryptophan, and so on.In this paper, we use different reducing agents to reduce graphene oxide.And it isbased on chmecial reduction metherd,which has many advantages such as simplicityof operation,producting graphene in lagre quantities and so on. This paper can bedivided into two parts, the first is based on a simple ionic liquid as a reducing agent,amides、ethylene glycol and isopropyl alcohol as cosolvents, to reduce and obtain themodified graphene. The second is the experimental exploration part, we use graphiteoxide as raw material, and test kinds of common reducing agents to investigate thereduction of the agents. This paper shows some common characterization and simpleanalyzing of the characterization.In chapter Ⅱ, we study on the preparation and characterization of graphite oxide,graphite oxide is mainly obtained by the method of Hummer, then we confirm thatproduction is graphite oxide through characterization of IR, TGA, XPS and Raman.Finally graphite oxide is under ultrasound and dispersed into amide solvents,isopropyl alcohol, ethylene glycol, water to prepare the single-layer graphene.we can conform that graphite oxide turn to the sheep-construction through SEM.Chapter III of this paper, we also study the methods of restored and modifiedgraphite oxide by simple ionic liquid and characterization. Ionic liquid can reducegraphite oxide in an accidental discovery. We also make preliminary experiment andfind the mass ratio of graphite oxide with ionic liquids. And we make furthercharacterization of the samples, such as XRD, TG, XPS, Raman and TEM. Throughcompare with the characterization of graphite oxide and the productions we confirmthe production is graphene. And ionic liquid is modified on the sheep-construction ofgraphene.On chapter Ⅵ, we take into account that traditional reductants which reducegraphite oxide has mostly toxic and pollutional problems. We departure from somereducing inorganic chemical reagents to reduce graphite oxide. We try to find somenon-toxic、pollution-free and green methods to restore the graphite oxide to graphene.Through reading and accumulation of large amounts of literature, we choosetryptophan as a pollution-free and green dispersant to inhibit of the reunion of thegraphene. And tryptophan belongs to amphoteric material, will be hydrolyzed with alarge amount of charge in the acidic or alkaline conditions. This determines that it has therole of the dispersant, so we selected tryptophan to inhibit the reduction process of graphenereunion.