Formic Acid oxidation on platinum- a simple mechanistic study

Published

July 15, 2015

Author(s)

Kathleen A. Schwarz, Ravishankar Sundararaman, Thomas P. Moffat, Thomas C. Allison

Abstract

The oxidation of organic acids on noble metal sur-faces is of importance for industrial processes and of academic interest, but the basic reaction mechanisms continue to be a matter of debate. Historically, mechanisms involving the formic acid molecule have been proposed, but recently a theory has been advanced that formate is the key reactant on the metal surface. 1 Ab initio calculations of this reaction on a Pt(111)surface have been performed to explore this reaction and help resolve the debate. When a formate molecule approaches the platinum surface from above, with the H pointing down, it re-acts to form CO 2 and adsorbed H. Furthermore, this reaction is nearly barrierless at relevant voltages on a clean Pt surface, but high coverages of adsorbates lead to large reaction bar- riers. This mechanism explains the elusiveness of an active surface intermediate, and leads to a proposed rate equation on the pristine metal proportional to the formate concentration times the number of available platinum sites; in practice the availability of these sites appears to limit the reaction.

Citation

Journal of the American Chemical Society

Pub Type

Journals

Keywords

formic acid oxidation, Pt, fuel cell, electrocatalysis

Citation

Schwarz, K. , Sundararaman, R. , Moffat, T. and Allison, T. (2015), Formic Acid oxidation on platinum- a simple mechanistic study, Journal of the American Chemical Society (Accessed December 10, 2023)