炭黑负载Pt-Fe双金属催化剂对甲醇的电催化氧化性能

Methanol Electrocatalytic Oxidation Performance of Carbon Black-supported Pt-Fe Bimetallic Catalyst

采用浸渍还原法制备了炭黑负载Pt及Pt-Fe双金属催化剂,通过X光衍射、扫描电镜及X射线光电子能谱对催化剂进行了表征.利用循环伏安法和计时电流法研究了溶液pH值和Pt/Fe原子比对Pt-Fe/C催化剂的甲醇电催化氧化活性与稳定性的影响.结果显示,当溶液pH值为9.0,Pt/Fe原子比为1∶1时,所得Pt-Fe/C催化剂对甲醇的电催化氧化活性与稳定性明显优于Pt/C催化剂.Fe的引入不仅提高了Pt粒子的分散与电化学活性表面积,而且有利于富Pt表面的形成,从而提高了Pt的有效利用率与催化性能.

Pt and Pt-Fe catalysts supported on carbon black with different Pt/Fe atomic ratios were prepared by a impregnation-reduction method. The samples were characterized by X-ray diffraction, scanning electron microsco- py, and X-ray photoelectron spectroscopy. The activity and stability for methanol electrocatalytic oxidation reaction were evaluated by cyclic voltammetry and chronoamperograms method, respectively. Effects of the various Pt/Au atomic ratios and different pH values during the preparation on the activities and stabilities were studied. The obtained Pt-Fe/C catalyst with Pt/Fe atomic ratio of 1 ： 1 at basic solution of pH 9 showed the better catalytic activity and stability than Pt/C catalyst. The results indicate that adding Fe to Pt/C catalyst can improve obviously the dispersion of Pt particles and its electrochemical surface area and form the rich-platinum surface structure and enhance its electrocatalytic activity and stability.