Gas-Liquid Interface Synthesis Of Noble Metal Alloy Catalysts For Application In Electrocatalysis

Noble metal-based alloy, such as Pt-based and Pd-based, exhibits superior catalytic properties, which makes it an ideal candidate as an electrocatalyst for both anodic and cathodic electrochemical reactions in fuel cells. However, its high price and scarcity are major issues for the successful deployment of commercial fuel cell systems. Thus, many efforts have been devoted to the construction of functional Pt-based and Pd-based materials with geometrical configurations, designed shape, and composition in view of achieving superior electrocatalytic properties and high precious-metal utilisations.Using inert gas as soft template, gas- liquid interface can be acted as the agglomeration/nucleation center of the nanocrystals with special morphology. This work presents a green, facile reaction to form a series of “clean” network- like alloy nanomaterials. We have studied the composition, morphology, structure and electrochemical properties of the prepared alloy nanoparticles, and have done the following work:Part ?: Preparation of PdNi P alloy nanoparticles networks for ethanol oxidationPd has excellent catalytic activity for ethanol oxidation reaction. The synergistic effect between nickel and other metallic element in the catalyst will futher enhance its activity. PdN iP alloy nanoparticle networks(PdN iP NN) were prepared by simultaneous reduction of PdC l2, NiC l2 and Na H2PO2 with NaBH4 via a gas- liquid interface reaction at room temperature using N2 bubbles. Through a variety of characterization, we have studied its structure composition and ethanol oxidation properties. The results show that PdN iP NN had markedly higher activity and durability for ethanol oxidation than PdN i nanoparticle networks and PdN iP grain aggregates.Part ?:Preparation of Pd Co P alloy nanoparticles networks for hydrazine electro-oxidationBoth Pd and Co have excellent catalytic activity for hydrazine electro-oxidation. The synergistic effect between Pd and Co will futher enhance its activity. PdCoP alloy nanoparticle networks(ANN) were prepared by simultaneous reduction of PdC l2, CoCl2 and NaH2PO2 with NaBH4 using N2 bubbles as soft-templates at room temperature. The PdCoP ANN porous structure was formed at the inert gas bubble surface, and could be obtained with varying ratios of precursors to produce catalysts with different compositions and catalytic activity. The results of the electrochemical performance show that PdCoP ANN produced markedly higher hydrazine oxidation activity than PdCo ANN and PdCoP grain aggregates, and catalytic activity varied with different ratios of Pd, Co and P.Part ?:Preparation of PtNi P alloy nanoparticles networks for hydrazine electro-oxidationAmorphous alloys possess the unique structures, are considered to be the candidate materials for fuel cell catalysts. is currently one of the candidate materials for fuel cell catalysts. Amorphous PtN iP alloy nanoparticle network structure is fabricated by gas- liquid interface reaction at different temperature(PtN iP-0, PtN iP-20, PtNiP-50 and PtN iP-80) as well as PtN i and Pt. Through a variety of characterization, we have studied its structure composition and the hydrazine electro-oxidation activity. The results of the electrochemical performance show that the amorphous PtN iP partial networks has better catalytic activity towards hydrazine oxidation compared to the Pt and PtNi networks,and PtNiP-50 has the optimal hydrazine oxidation and stability.