Synthesis And Electrocatalytic Activity Performance Of PtSn/C Electrocatalysts For Direct Ethanol Fuel Cell

Recently, direct ethanol fuel cells have received much attention due to their high power energy density, low cost, wide range of fuel sources and the convenient storage/delivery qualities.Catalysts as the core components of the fuel cell which is the key to improve energy conversion efficiency of direct ethanol fuel cell. At present, the most widely used catalysts is Pt/C, because during the oxidation process Pt is very active for C-C bond cleavage in the EOR and makes the oxidation process more thoroughly.However, the scarcity and high cost of Pt, as well as the easily poisoning of Pt surfaces upon formation of reaction intermediates, limits the industrial applications of DEFCs.Therefore, developing more efficient Pt-based catalysts with enhanced catalytic activity and improved stability is the main research direction.In this paper, Pt Sn/C electrocatalyst was synthesized quikly using microfluidic capillary reaction system,and electrocatalytic activity of the electrocatalysts have also been studied. The detailed research contents and corresponding results are summarized into the following two parts.1?First, microfluidic capillary reation system was built and used as the synthesis method for fuel cell catalysts.Under ethylene glycol conditons, Pt Sn/XC-72?Pt Sn/CNT?Pt Sn/r GO alloy catalysts were synthesized by using chloroplatinic acid(H2Pt Cl6?6H2O) and tin tetrachloride(Sn Cl4?5H2O) as the metal precursors, XC-72?CNT and r GO were used as carbon supports. The structure, morphology and elemental composition of the as-prepared catalysts was characterized by X-ray diffraction(XRD),Transmission elctron microscopy(TEM),and inductively coupled plasma atomic emission spectroscopy(ICP-AES).The results show that all the as-prepared Pt Sn alloy NPs have very uniform loading and narrow size distribution on the various carbon surface.Electrochemical testing results show that all the as-prepared Pt Sn/C catalysts have enhanced electrocatalytic activity and improved stability for ethanol oxidation reaction under acid condition.2?Pure phase Pt Sn/C intermetallic compounds were synthesized by microfluidic capillary reaction system and the synthesis conditions were explored and optimized.The study revealed that reaction temperature,type of precursor and precursor metal ratios have significant effect on the synthesis of pure phase Pt Sn/C intermetallic cimpounds.Under polyethylene glycol 400 solvent system, In the experiment of using chloroplatinic acid and tin tetrachloride as precursor, regulated the reaction temperature and precursor ratios can achive the synthesis of Pure phase Pt Sn/C intermetallic compounds.When the temperature was 400 oC, Pt:Sn=1:100, the pure phase Pt Sn/C intermetallic compounds was achived.Under 350 oC conditions,in the experiment of changing precursor species we found that a combination of different precursor compounds can regulate the the purity of Pt Sn/C intermetallic compounds.When Pt:Sn=1:3, choosed platinum acetylacetonate and tin tetrachloride as precursor can also achive pure phase Pt Sn/C intermetallic compounds.The synthesized Pt Sn/C intermetallic compounds by using acetylacetonate and tin tetrachloride as precursor were tested for electrochmiacal activity. The results showed that Pt Sn / C intermetallic compounds having good oxygen reduction performance.