期刊
ELECTROCHIMICA ACTA
卷 50, 期 10, 页码 1973-1983出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.electacta.2004.09.006
关键词
Pt nanoparticles; citric acid stabilizer; methanol electrooxidaton; oxygen electroreduction; direct methanol fuel cell (DMFC)
Pt/C nanocatalysts were prepared by the reduction of chloroplatinic acid with sodium borohydride, with citric acid as a stabilizing agent in ammonium hydroxide solution. These nanocatalysts were obtained by altering the molar ratio of citric acid to chloroplatinic acid (CA/Pt) from 1:1, 2:1, 3:1 to 4:1. Transmission electron microscopy and X-ray diffraction analyses indicated that the well-dispersed Pt nanoparticles of around 3.82 nm in size were obtained when the CA/Pt ratio was maintained at 2:1. X-ray photoelectron spectroscopy measurements revealed that the 2:1, 3:1 and 4:1 molar ratio catalysts had a relatively higher amount of Pt in their metallic state than did the 1:1 molar ratio catalyst. Cyclic voltammetry results demonstrated that the Pt/C nanocatalysts annealed at 400degreesC in an N-2 atm provided higher electrocatalytic activity. Among all the molar ratio catalysts, the 2:1 molar ratio catalyst exhibited the largest electrochemical active surface (EAS) area, and its methanol oxidation reaction current was superior to the E-TEK catalyst. The oxygen reduction reaction of the catalysts studied by linear sweep voltammetry and tested in a fuel cell indicated that the catalytic activity of the 2:1 molar ratio catalyst was comparable to that of an E-TEK catalyst. (C) 2004 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据