Carbon-supported platinum catalysts were prepared by NaBH4 reduction of metal precursors and the CeO2 nanoparticles were prepared by citric acid sol-gel method. The structure and morphology of two kinds of nanoparticles were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM), respectively. The Pt particles were uniformly dispersed on the carbon surface and showed the rod-like morphology. The CeO2 was spherical in shape. The appropriate amount of CeO2 nanoparticles was added into Pt/C systems to improve activity of the catalysts. Several electrochemical techniques such as cyclic voltammogram (CV), chronoamperometry (l-t) and electrochemical impedance spectroscopy (EIS) were used to investigate the properties of CeOe-PVC catalysts for methanol electrooxidation in 1 mol/L CH3OH+0.SH2SO4 aqueous solutions. The results revealed that compared with Pt/C catalysts CeO2-Pt/C exhibited a higher activity and stability for methanol electro-oxidation. Moreover, the effect of CeO2 content on the activity of Pt/C catalysts was discussed in detail.
In the present work,tert-butylhydroquinone(TBHQ) was used to decorate graphene nanosheets to obtain a novel and environmentally friendly electrode material for supercapacitors.The fast redox reactions between hydroquinone and quinone generate pseudocapacitance.Graphene layers which have adsorbed TBHQ interact with each other to construct a three-dimensional network.Through this network,electrolyte ions can easily access the surface of graphene to generate electric double-layer capacitance.Electrochemical measurements have shown that using TBHQ as a redox modifier of graphene can obtain a maximum value of 302 F g-1 and provide a 51% enhancement in specific capacitance.Furthermore,excellent rate capability and cycling ability are achieved using the TBHQ-decorated graphene nanosheet electrode.
WANG HuanWen WU HongYing CHANG YanQin CHEN YanLi HU ZhongAi