Fundamental Mechanistic Understanding of Electrocatalysis of Oxygen Reduction on Pt and Non-Pt Surfaces : Acid versus Alkaline Media
Joint Authors
Mukerjee, Sanjeev
Ramaswamy, Nagappan
Source
Advances in Physical Chemistry
Issue
Vol. 2012, Issue 2012 (31 Dec. 2012), pp.1-17, 17 p.
Publisher
Hindawi Publishing Corporation
Publication Date
2012-03-20
Country of Publication
Egypt
No. of Pages
17
Main Subjects
Abstract EN
Complex electrochemical reactions such as Oxygen Reduction Reaction (ORR) involving multi-electron transfer is an electrocatalytic inner-sphere electron transfer process that exhibit strong dependence on the nature of the electrode surface.
This criterion (along with required stability in acidic electrolytes) has largely limited ORR catalysts to the platinum-based surfaces.
New evidence in alkaline media, discussed here, throws light on the involvement of surface-independent outer-sphere electron transfer component in the overall electrocatalytic process.
This surface non-specificity gives rise to the possibility of using a wide-range of non-noble metal surfaces as electrode materials for ORR in alkaline media.
However, this outer-sphere process predominantly leads only to peroxide intermediate as the final product.
The importance of promoting the electrocatalytic inner-sphere electron transfer by facilitation of direct adsorption of molecular oxygen on the active site is emphasized by using pyrolyzed metal porphyrins as electrocatalysts.
A comparison of ORR reaction mechanisms between acidic and alkaline conditions is elucidated here.
The primary advantage of performing ORR in alkaline media is found to be the enhanced activation of the peroxide intermediate on the active site that enables the complete four-electron transfer.
ORR reaction schemes involving both outer- and inner-sphere electron transfer mechanisms are proposed.
American Psychological Association (APA)
Ramaswamy, Nagappan& Mukerjee, Sanjeev. 2012. Fundamental Mechanistic Understanding of Electrocatalysis of Oxygen Reduction on Pt and Non-Pt Surfaces : Acid versus Alkaline Media. Advances in Physical Chemistry،Vol. 2012, no. 2012, pp.1-17.
https://search.emarefa.net/detail/BIM-475869
Modern Language Association (MLA)
Ramaswamy, Nagappan& Mukerjee, Sanjeev. Fundamental Mechanistic Understanding of Electrocatalysis of Oxygen Reduction on Pt and Non-Pt Surfaces : Acid versus Alkaline Media. Advances in Physical Chemistry No. 2012 (2012), pp.1-17.
https://search.emarefa.net/detail/BIM-475869
American Medical Association (AMA)
Ramaswamy, Nagappan& Mukerjee, Sanjeev. Fundamental Mechanistic Understanding of Electrocatalysis of Oxygen Reduction on Pt and Non-Pt Surfaces : Acid versus Alkaline Media. Advances in Physical Chemistry. 2012. Vol. 2012, no. 2012, pp.1-17.
https://search.emarefa.net/detail/BIM-475869
Data Type
Journal Articles
Language
English
Notes
Includes bibliographical references
Record ID
BIM-475869