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采用一步还原法(乙二醇为还原剂)与两步还原法(在聚乙烯吡咯烷酮PVP保护下,先用硼氢化钠还原制备Sn溶胶,沉积Pt后用乙二醇还原)制备了炭黑负载Pt-Sn双金属催化剂,利用循环伏安法和计时电流法考察了催化剂制备方法、Pt/Sn原子比、溶液p H值、PVP/Sn质量比、反应介质等对乙醇室温电催化氧化活性和稳定性的影响.以X光衍射、透射电镜及电化学活性面积测定对所得催化剂进行了表征.发现引入Sn明显提高了Pt催化剂对乙醇的电催化活性与稳定性,两步还原法得到的Pt3Sn/C催化剂具有更小的颗粒尺寸,更大的电化学活性面积及更高的乙醇氧化活性与稳定性.与酸性介质相比,该催化剂在碱性介质中的电化学活性更好.
A one-step reduction method (ethylene glycol as reductant) and a two-step reduction method (under the protection of polyvinylpyrrolidone PVP, sodium borohydride was used to prepare Sn sol, Pt was deposited and then reduced with ethylene glycol) Pt-Sn bimetallic catalyst, the preparation method of the catalyst, the Pt / Sn atomic ratio, the solution p H value, the mass ratio of PVP / Sn and the reaction medium were investigated by cyclic voltammetry and chronoamperometry. The stability of the catalyst was characterized by X-ray diffraction, transmission electron microscopy and electrochemically active area determination. It was found that the introduction of Sn significantly enhanced the electrocatalytic activity and stability of Pt catalyst on ethanol. The Pt3Sn / C catalyst has a smaller particle size, a larger electrochemically active area, and a higher ethanol oxidation activity and stability, which is more electrochemically active in alkaline media than acidic media.