Preparation And Electrochemical Properties Of The Graphene Oxide Loaded With Metal Sulfides (cds, Zns)

Owing to unique physical properties, nanostructual metal sulfides have exhibited promising applications in many fields such as optics, sensors, catalysis and electrics. Graphite oxide(GO) is a typical two-dimensional layered nanomaterial with plenty of functional groups (such as hydroxyl, carboxyl, carbonyl, epoxy groups) on its sruface, bestowing it with rich intercalation properties. The combination of GO with metal sulfide nanocrystals may result in improved electrochemical properties.In this work, a composite of GO decorated with tetrapods-CdS nanoparticles (tetrapods-CdS/GO) was firstly fabricated via a solvothermal method using ethylenediamine (en) as the solvent. The effects of reaction parameters (sulfide precursors and the addition of De-ioned water) on the morphology and texture of as-obtained products were considered. It showed that tetrapods-CdS/GO was synthesized solvothermally at 120℃for 12h, by using Cd(CH3COO)2-2H2O and Na2S·9H2O as raw materials, pure en as solvent.Taking into account of the facts that solvent exerts a great influnce on the microsturctue of as-synthesized products. Different solvents, like ethonal,ethylene glycol and DMF, were considered as the compensatory system for preparing GO-CdS nanocomposites. Some reaction parameters, like sulfur sources and dispersant was also discussed. The possible mechanism was discussed.On the basis of above experiments, the GO-zinc sulfide nanocomposites (ZnS/GO) were fabricated in the ethanol and DMF system, with the influence of sulfur source and dispersant into consideration. It showed that the well dispersed ZnS/GO was synthesized solvothermally at 140℃for 24h, by using Zn(CH3COO)2·2H2O and Na2S·9H2O as raw materials, EDTA as surfactant, ethanol as solvent.The electrochemical properties of the samples were studied with cyclic voltammetris (CV). The results indicat that the as-obtained composites (CdS/GO and ZnS/GO) have a superor specific-capacitance as well as electeochemcial stabilities than their individual components (CdS, ZnS, and GO). The dispersibility and microstructrue of metal sulfide on GO play a vital role in their electrochemical activities.