Green Techniques For Reduction Of Graphene Oxide And Research Of Its Application

Graphene has attracted a great deal of attention in recent years due to itsexcellent physical and chemical properties. Its potential applications include catalystsupports, nanoelectronic devices, batteries, supercapacitors, composite materials,biological detection devices, et al. However, these potential applications are limitedbecause it is difcult to produce grapheme nanosheets on a large scale. The existingmethods of preparation of graphene are most complex and difficult to control theprocess, or difficult to realize industrialization, which results in high costs. Therefore,an effective and controllable method to synthesize large-scale and high-qualitygraphene is highly desirable.The chemical reduction of graphene oxide (GO) is an efficient and simplemethod of preparation of graphene, but most reagents are hazardous or poisonous,therefore their use is not desirable for the large-scale production of reduced grapheneoxide (RGO). In this paper, an easy and environmentally friendly approach for thereduction of GO is reported. We used L-Lysine (L-Lys), L-arginine (L-Arg) and L-Serine (L-Ser) as the reductants, and carboxy methyl starch (CMS), carboxyl methylcellulose (CMC) and yellow dextrinas (YD) as the stabilizing agents, and synthesizethe stable suspended RGO successfully. The reduction of the GO was verified byFourier transform infrared spectroscopy, X-ray difraction, thermo-gravimetricanalysis, Raman spectroscopy and X-ray photoelectron spectroscopy, et al. Orderedporous RGO/CMS and RGO/CMC foams were prepared by a unidirectionalfreeze-drying method and used as adsorbents for heavy metal ions and dye. AfterRGO/CMC foams were used to adsorb Cu ions, the foams were then treated withsodium borohydride to transform Cu ions into nanoparticles. These Cunanoparticle-containing RGO/CMC foams showed superior catalytic performance forthe reduction of4-nitrophenol. So this method offers a way to turn a recovered wastematerial into something useful. The RGO prepared by L-Ser as the reductant and YDas the stabilizing agent showed excellent performance in drug delivery.A simple route for the reduction of GO by using Cd powder as a reducing agentwas also developed. Meanwhile, the by-products of the reduction, Cd2+was made full use of to prepare CdO/RGO hybrids. The electrochemical capacitive behaviors of theCdO/RGO hybrid as the electrode material in a supercapacitor were determined bycyclic voltammetry and galvanostatic charge/discharge methods. The CdO/RGOhybrid showed excellent electrochemical properties in supercapacitor electrodeapplications.