壳聚糖修饰炭黑负载Pt-Au催化剂对甲醇氧化的电催化性能

以炭黑及自制的壳聚糖-炭黑(CHI-C)复合材料为载体,采用溶胶负载法制备了Pt_m＾Au/C及Pt_m＾Au/CHI-C催化剂(＾ 代表Au、Pt为分步负载,m代表Pt/Au原子比),通过紫外-可见吸收光谱、X射线衍射、透射电镜及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分别测定了Pt-Au催化剂对甲醇电催化氧化反应的活性和稳定性,考查了Pt/Au原子比及CHI改性对电催化活性和稳定性的影响。结果表明,Pt_1.0＾Au/C具有最高的催化活性,炭黑中加入少量CHI能提高Pt_1.0＾Au/C催化剂的稳定性。

Electrocatalytic performance of Pt-Au catalysts supported on chitosan-modified carbon black for methanol oxidation

Chitosan-carbon composite material (CHI-C) was prepared. Pt-Au catalysts supported on chitosan-modified carbon black with different Pt/Au atomic ratios were prepared by a sol immobilization method. The samples were characterized by UV-visible absorption spectroscopy, X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy. The activity and stability for methanol electrocatalytic oxidation reaction were evaluated by cyclic voltammetry and chronoamperograms, respectively. The effects of Pt/Au atomic ratios and chitosan modification on the activities and stabilities were studied. As a result, Pt_1.0＾Au/C catalyst showed the best catalytic activity. Adding small amount CHI to carbon black support can improve the stability of Pt_1.0＾Au/C catalyst.