AC impedance investigation of plating potentials on the catalytic activities of Pt nanocatalysts for methanol electrooxidation

详细信息    查看全文

• 作者：Tao Huang ; Rongrong Jiang ; Deng Zhang ; Jihua Zhuang ; Wenbin Cai and Aishui Yu
• 关键词：Methanol oxidation ; Pt nanoparticles ; Electrocatalyst ; Electrochemical impedance spectroscopy
• 刊名：Journal of Solid State Electrochemistry
• 出版年：2010
• 出版时间：January, 2010
• 年：2010
• 卷：14
• 期：1
• 页码：101-107
• 全文大小：827.9 KB

文摘

Pt nanocatalysts supported on glassy carbon (GC) were electrochemically deposited by cyclic voltammetry (CV) with different scanning potential ranges. The lower limit of potential was fixed at −0.25 V vs. saturated calomel electrode, whereas the upper limit of potential was adjusted to be 0.0, 0.20, 0.60, and 1.0 V. Scanning electron microscopy images showed that Pt microparticles are uniformly dispersed on the GC substrate and the agglomerated microparticles are composed of numerous nanoparticles. In addition, the catalytic capabilities of Pt/GCs for methanol electrooxidation were examined by CV, chronoamperometry, and electrochemical impedance spectroscopy in a solution of 0.5 M CH₃OH and 0.5 M H₂SO₄. The results demonstrate that the catalytic activities and stabilities of Pt catalysts prepared by the potential ranges from −0.25 to both 0.60 and 1.0 V for methanol electrooxidation were higher than the others, which may be due to their higher electrochemical active surface area, lower charge transfer resistance, and more preferred Pt crystallographic orientation.