Preparation And Performance Of Graphene As Support Of Palladium Based Catalysts

Graphene is a new type of carbon materials. Because of its unique graphite flatstructure, good electrical conductivity (10³-10⁴S m^-1) and large specific surface area(2630m²g^-1), is increasingly used for electric catalyst support. This paper the graphenesupported Pd（Pd/Gr） catalysts was prepared, and the formic acid oxidation on Pd/Grcatalysts electrod was studied. The catalyst characterization was investigated bytransmission electron microscopy （TEM）, X-ray diffraction （XRD） and electrochemicalmethods such as specific surface area （ESA）. The electrochemical properties of thecatalyst are studied using the linear sweep method, cyclic voltammetry,chronoamperometry and testing technology.In this paper, the Pd/Graphene nano catalyst was prepared and the Pd nanoparticlessize is about4.7nm. In the same conditions and same metal loading, compared with thePd/C catalyst electrode, Pd/Graphene electrode exhibits higher catalytic activity for theoxidation of formic. On the Pd/Graphene electrodes, formic acid oxidation peak currentdensity is1.8times of Pd/C electrode. High load catalyst showed the advantages ofgraphene support. By comparing the Pd/GraPhene electrode electrochemical specificsurface area and stability is further evidence that Pd/GraPhene nano catalyst for formicacid oxidation is better than that of Pd/C catalyst. Stability results show that thePd/Graphene electrode has better stability than Pd/C.Pd/Graphene catalyst was prepared respectively under different system and differentdosage of ethylene glycol and surfactant. Experimental results show that the dosage ofalcohol in the water system of ethylene glycol for20ml in the preparation ofPd/Graphene has high catalytic activity and good stability. Under the condition of thepreparation of Pd/Graphene catalyst, Pd particle size of4.7nm. The surfactant ofsodium citrate during the preparation of the catalysts also has a certain role in promotingmetal particle dispersion.This paper also studied the different Pd: Pt atom ratio of Pd-Pt/Graphene catalyst forelectrocatalytic oxidation of methanol, ethanol and formic acid. In addition the effect ofultrasonic shock during the catalyst preparation is also investigated.