Synthesis And Electrocatalytic Performance Investigation Of Platinum-based Nanocomposites

Since the 20th century,the development of science and technology increasingly progress,and fossil fuel promoted the progress of human civilization,along with the use of fossil fuel energy shortage and environmental pollution and other issues also arises at the historic moment.Nowadays more and more countries bring sustainable development strategy into country's policies,exploiting the new energy which is green clean,efficient and sustainable development.Direct methanol fuel cell?DMFC?as a new way of energy supply electrochemical device in which uses methanol as fuel,proton exchange membrane as electrolyte solution and easy to operate,high efficiency.Methanol is a kind of new material energy can be obtained from biomass materials such as straw fermentation,with abundant sources,the safety storage and transportation,and the low price,at the same time in the process of energy conversion only emissions of CO₂ and H₂O on the environment pollution-free.Electrode material,which is the core of the DMFCS equipment that have search widely and high catalytic efficiency of throw is Pt,Pd and other noble metals.However,the high cost and limited reserve of noble metals easy to CO poisoning make catalytic activity falling and severely hider the eventual practical commercialization of DFMCs.At present the study found that Pt by alloying with inexpensive transition metals,such as Co,Ni,Cu,etc.or carbon materials one effective approach to reduces the cost as catalysts but also improve the ability overcome CO poisoning and display superior catalytic performance.This article mainly introduced the synthesis of DMFC anode material,the preparation of the Pt-Cu nanoclusters,nanoflowers or Pt load of nitrogen doped mesoporous carbon materials,and to explore its ability of methanol catalytic oxidation under the condition of acidic or alkaline solution environment.The main content is divided into the following three parts:?1?Synthesis and electrocatalytic performance investigation of Pt-Cu nanoflowers?Pt-Cu NFs?Several high quality nanoflowers structures have been synthesized by one-pot synthesis method.In the process,CTAB and NaI serving as the stabilizing agent and shape-control agent,were added to tune the formation of nanoflowers 3D superstructures.Through a series of tests on the structure characterization,and explore its sense of alcohol and catalytic activity of the ethanol solution in alkaline solution.The results showed that Pt-Cu NFs exhibit superior MOR activity and long-term durability compared to Pt NCs.?2?Synthesis and electrocatalytic performance investigation of Pt-Cu nanoclusters?Pt-Cu BANCs?Several high quality Pt-Cu nanospheres structures have been synthesized by a one-pot synthesis method.Poly?diallyldimethylammonium chloride?PDDA was presumed as reluctant and stabilizing agent to ensured the formation of isolated Pt crystal nuclei.The XRD patterns further indicate the alloy structures of the clusters,calculations using the Debye-Scherrer formula for the crystal size of about 6 nm.When adding 80 mg of NaI into the typical experiment,the product is urchin-like hierarchical structure with an average dimension of 1?m.When adding 480 mg of NaI into the typical experiment,the product is smooth ball structure.The electrochemical catalytic activity of these Pt-Cu NCs towards methanol oxidation was also evaluated in comparison with the activity of commercial Pt/C and Pt black.Electrochemical measurements demonstrate that Pt-Cu NCs exhibit superior MOR activity and long-term durability compared to commercial Pt black and Pt/C and have better stability ability.?3?Pt based compound nitrogen doped carbon material synthesis and methanol catalyst performance studyBiomass-derived nitrogen doped carbon-based catalyst prepared by carbonization and activation method,using carbon material of biomass silkworm was used as precursor,using MgO as the template for the porous treatment of the material.The catalyst has high specific surface are high up to 1130 m²g^-1,with the doping nitrogen conrtent of 5 wt%.In this study,a new ethylene glycol reduction method was used to deposit Pt NPs on nitrogen doped carbon-based materials,its catalytic methanol performance tests by using cyclic voltammetry,the catalyst exhibits excellent catalytic activity towards catalytic methanol compared with platinum loading Cabot carbon catalyst in acid methanol solution,the experimental results showed that the catalyst has such good catalytic activity and stability.