The Preparation Of Noble Metal Nanomaterials And Their Electrocatalytic

Nanomaterials exhibit unique electronic, optical, thermal and catalytic properties. Noble metal nanomaterials possess exceeding advantages over other nanomaterials including stability, conductivity, biocompatibility and size-related magnetic and optical properties. Through effectively controlling the size, shape and composition of noble metal nanomaterials, we can enhance their catalytic performance. In this paper, we are focused on studying the synthesis and application of noble metal nanomaterials in direct alcohol fuel cells and electrochemical sensors, the main contents are followed:(1) flower-like PtAg alloys uniformly supported on reduced graphene oxide nanosheeets (denoted as Pt-Ag/RGO) were prepared via a simple and facile one-pot solvothermal method with the assistance of ionic liquid crystal (1-hexadecyl-2,3-dimethylimidazolium bromide, [Ci6MMIm]Br) as a capping agent and a structure directing agent. The as-prepared nanocomposites own a larger active surface area, better electrocatalytic activity, higher methanol tolerant activity and longer-term durability toward oxygen reduction reaction, compared with commercial Pt black, Pt-C (10 wt%) and RGO catalysts.(2) Au-Pt nanochains supported on reduced graphene oxide nanosheets (denoted as Au-Pt/RGO) were prepared via a simple, rapid and facile one-step co-reduction method with the assistance of caffeine as a capping agent and a structure directing agent. The as-prepared nanocomposites display enlarged electrochemical active surface area, significantly enhanced catalytic activity and better stability for methanol and ethylene glycol oxidation, compared with commercial Pt black and Pt-C catalysts.(3) Pt@Pd core-shell nanoparticles supported on reduced graphene oxide (denoted as Pt-Pd/RGO) were synthesized by a facile, rapid and without any template method with the assistance of caffeine as a structure-directing agent and a capping agent. The as-synthesized Pt-Pd/RGO shows the enlarged electrochemically active surface area, remarkably enhanced catalytic activity and improved stability for methanol oxidation reaction, compared to Pt/RGO, Pd/RGO, commercial Pt black and Pd black catalysts.(4) Pd-Au nanochain supported on reduced graphene oxide (denoted as Pd-Au/RGO) were prepared via a simple and straightforward co-chemical reduction method with the assistance of caffeine as a capping agent and a structure directing agent. The as-prepared nanocomposites exhibited much better electrocatalytic performance than that of conventional Pd black and Pd-C catalysts towards oxygen reduction reaction.(5) Porous gold nanosheets modified glassy carbon electrode (GCE) was facilely prepared by one-step electrodeposition, using N-methylimidazole as a growth-directing agent. The electrocatalytic property of the modified GCE was examined by selective and simultaneous detection of dopamine (DA) and acetaminophen (AC) as model systems. The oxidation peak currents linearly increased with the concentrations of DA and AC in the ranges from 2.0 to 298.0 μM and 3.0 to 320.0 μM, respectively, and the detection limits are 0.28 μM for DA and 0.23μMfor AC(S/N=3).