Methanol Oxidation at Platinum in Alkaline Media: A Study of the Effects of Hydroxide Concentration and of Mass Transport

Abstract

The hydroxide ion concentration dependence of the methanol oxidation reaction at Pt was studied using microelectrode voltammetry and rotating disk electrode voltammetry. Both methods suggest that the rate of methanol oxidation is limited by hydroxide mass transport at low hydroxide concentrations, while it is inhibited by hydroxide adsorption at high concentrations. It was possible to shift from the transport‐limited regime to the inhibitory regime by varying the bulk concentration of hydroxide or by varying mass transport to the electrode. Rotating ring‐disk electrode voltammetry was employed to qualitatively assess changes in the diffusion layer pH. The results indicated a decrease in the surface pH during methanol oxidation, as expected, but also that the pH reached a steady state during hydroxide transport limited methanol oxidation.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jun 04, 2021
Source ID
10.1002/cphc.202100087

Entities

People

  • Eric D Rus
  • Hongsen Wang
  • Héctor D. Abruña
  • Ryo H. Wakabayashi

Organizations

  • Air Force Office of Scientific Research
  • Cornell University

Tags

Fields of Study

  • Chemistry

Readers

  • Electrochemical Engineering/ Fuel Cell Technologies