CATALYSIS INELECTROCHEMISTRY

Wiley Series on Electrocatalysis and Electrochemistry

Andrzej Wieckowski, Series Editor

Fuel Cell Catalysis: A Surface Science Approach, Marc T. M. Koper

Electrochemistry of Functional Supramolecular Systems, Margherita Venturi, PaolaCeroni, and Alberto Credi

Fuel Cell Science: Theory, Fundamentals, and Biocatalysis, Andrzej Wieckowskiand Jens Nørskov

Catalysis in Electrochemistry: From Fundamentals to Strategies for Fuel CellDevelopment, Elizabeth Santos and Wolfgang Schmickler

CATALYSIS INELECTROCHEMISTRYFROM FUNDAMENTALS TOSTRATEGIES FOR FUEL CELLDEVELOPMENT

Edited by

Elizabeth SantosWolfgang Schmickler

Copyright © 2011 John Wiley & Sons, Inc. All rights reserved.

Published by John Wiley & Sons, Inc., Hoboken, New JerseyPublished simultaneously in Canada

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Library of Congress Cataloging-in-Publication Data:

Santos, ElizabethCatalysis in electrochemistry : from fundamentals to strategies for fuel cell development / edited by

Elizabeth Santos and Wolfgang Schmicklerp. cm.

Includes bibliographical references and index.ISBN 978-0-470-40690-8 (cloth)

Printed in Singapore

eBook ISBN: 978-0-470-92941-4oBook ISBN: 978-0-470-92942-1ePub ISBN: 978-0-470-93473-9

10 9 8 7 6 5 4 3 2 1

To Cristina Giordano and Wolf Vielstich,Our Mentors and Parents in Science

E.S. and W.S.

CONTENTS

Preface ix

Preface to the Wiley Series on Electrocatalysis and Electrochemistry xi

Contributors xiii

1. Volcano Curves in Electrochemistry 1Roger Parsons

2. Electrocatalysis: A Survey of Fundamental Concepts 17Alejandro Jorge Arvia, Agustın Eduardo Bolzán, and Miguel Angel Pasquale

3. Dynamics and Stability of Surface Structures 67Margret Giesen and Guillermo Beltramo

4. Electrocatalytic Properties of Stepped Surfaces 127Juan M. Feliu, Enrique Herrero, and Vıctor Climent

5. Computational Chemistry Applied to Reactions inElectrocatalysis 165Axel Gross and Sebastian Schnur

6. Catalysis of Electron Transfer at Metal Electrodes 197Elizabeth Santos and Wolfgang Schmickler

7. Combining Vibrational Spectroscopy and Density FunctionalTheory for Probing Electrosorption and Electrocatalytic Reactions 223Marc T. M. Koper

8. Electrochemical Catalysts: From Electrocatalysis toBioelectrocatalysis 249Alejandro Jorge Arvia, Agustın Eduardo Bolzan, and Miguel Angel Pasquale

9. Electrocatalysis at Bimetallic Surfaces Obtainedby Surface Decoration 297Helmut Baltruschat, Siegfried Ernst, and Nicky Bogolowski

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viii CONTENTS

10. CO Adsorption on Platinum Electrodes 339Ángel Cuesta and Claudio Gutiérrez

11. Exploring Metal Oxides: A Theoretical Approach 375Monica Calatayud and Frederik Tielens

12. Electrocatalysis at Liquid–Liquid Interfaces 427Bin Su, Hubert H. Girault, and Zdenek Samec

13. Platinum-Based Supported Nanocatalysts for Oxidation ofMethanol and Ethanol 453Ernesto R. Gonzalez, Edson A. Ticianelli, and Ermete Antolini

14. Impact of Electrochemical Science on Energy Problems 487Elizabeth Santos and Wolfgang Schmickler

Index 499

PREFACE

By many, Professor Wolf Vielstich is con-sidered to be the father of modern fuel cellresearch. His originally German textbookBrennstoffelemente, which appeared in1965, was quickly translated into Russian,English (Fuel Cells, Wiley, 1970), andSpanish and is a classic. Even today, itis an excellent source for the scientificbackground behind electrochemical energyconversion. In total, Professor Vielstich hasbeen active in fuel cell research for morethan 50 years, and only a few years ago hebegan to edit, together with A. Lamm , H. Yokokawa, and H. Gasteiger, the Handbookof Fuel Cells—Fundamentals, Technology, Applications, whose last volumes have justbeen published. We interviewed him electronically at his home in Salta, Argentina.

INTERVIEW WITH WOLF VIELSTICH

What made you become interested in fuel cells as early as the 1950s?During the early 1950s, when I was still a student, I worked at theRuhrchemie-Oberhausen during vacations. There, in cooperation with ProfessorJusti, Braunschweig, experiments on high-temperature FCs were in progress, whileI worked on alkaline H2/O2 cells at low temperatures. Then, in the 1960s, it was agood idea to choose H2/O2 cells, with liquid reactants, for electric power and watersupply (from the cell reaction) for the NASA Apollo programm. The Wernher vonBraun organization asked my advice about introducing a 1- to 2-kW FC unit, and Isuggested Dr. Jose Giner from our Electrochemistry Department at Bonn Universityto do the job. It was a success, and NASA is still using this alkaline FC today.

Since that time there has been an ebb and flow in fuel cell activities. What arethe perspectives at present?During the last 10 years, the automobile industry, including General Motors andDaimler, has been optimistic about developing an acid-type H2–air unit for applicationin electric cars. But up to now, costs of production are still too high, and in additionthe supply of hydrogen in the form of gas or liquid is an unsolved problem.

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x PREFACE

What is the most promising fuel for fuel cells: hydrogen, methanol, somethingelse?While power density and energy capacity are satisfactory in the case of H2/O2 cells,as has been demonstrated by their recent use in motorgliders (DLR-MotorseglerAntares), this is not at all the case for methanol or ethanol.

At present, there is much activity in fuel cell research. What are the challengesfor fundamental science in this area today?Nowadays, much fundamental fuel cell research is focused on the catalysis ofmethanol and ethanol oxidation at temperatures below 80◦C. Theoretically, with oxi-dation to CO2, methanol can deliver six e− per molecule; at present, commercialcells deliver 250 mA cm−2 and a cell voltage of 400 mV at 60◦C, and the six e− permolecule is almost attained. But for application in electric cars a factor of at least 4 to5 in power density would be necessary. Using ethanol, present-day catalysts show aneven lower energy density than with methanol and offer no more than 2–3 electronsper molecule, while the complete oxidation to CO2 involves 12 electrons. A catalystbreaking the C–C bond has still to be found.

This year, the first commercial all-electric cars, heavily subsidized, have beenmarketed in Japan. Are they just a marketing hype or are they already a viablealternative to conventional cars?All-electric cars, using Li ion batteries, still have a problem. Due to the high costs, onlysmall cars with limited power and energy capacity are being built. Hybrid systems,as produced by Toyota today, use only small battery sets; this makes sense in thisparticular application.

What role will electric cars play in 20 years time? Which technologies will theyuse: fuel cells, batteries, or a combination of both?Without a marked change in the availability of gas and/or oil, even in 20 years timeall-electric cars, using fuel cells or batteries, will make only a small contribution,mainly due to the high production costs.

E. Santos

W. Schmickler

PREFACE TO THE WILEY SERIES ONELECTROCATALYSIS AND ELECTROCHEMISTRY

The Wiley Series on Electrocatalysis and Electrochemistry covers recent advances inelectrocatalysis and electrochemistry and depicts prospects for their contribution tothe industrial world. The series illustrates the transition of electrochemical sciencesfrom its beginnings in physical electrochemistry (covering mainly electron trans-fer reactions, concepts of electrode potentials, and structure of the electrical doublelayer) to a filed in which electrochemical reactivity is shown as a unique aspect ofheterogeneous catalysis, is supported by high-level theory, connects to other areasof science, and focuses on electrode surface structure, reaction environments, andinterfacial spectroscopy.

The scope of this series ranges from electrocatalysis (practice, theory, relevanceto fuel cell science and technology) to electrochemical charge transfer reactions,biocatalysis and photoelectrochemistry. While individual volumes may appear quitediverse, the series promises up-to-date and synergistic reports on insights to furtherthe understanding of properties of electrified solid/liquid systems. Readers of theseries will also find strong refernce to theoretical approaches for predicting elec-trocatalytic reactivity by high-level theories such as DFT. Beyond the theoreticalperspective, further vehicles for growth are provided by the sound experimentalbackground and demonstration of the significance of such topics as energy storage,syntheses of catalytic materials via rational design, nanometer-scale technologies,prospects in electrosynthesis, new research instrumentation, surface modifications inbasic research on charge transfer and related interfacial reactivity. In this context,one might notice that new methods that are being developed for one specific field arereadily adapted for application in another.

Electrochemistry has benefited from numerous monographs and review articlesdue to its applicability in the practical world. Electrocatalysis has also been the sub-ject of individual reviews and compilations. The Wiley Series on Electrocatalysis andElectrochemistry hopes to address the current activity in both of these complementaryfields by containing volumes that individually focus on topics of current and poten-tial interest and application. At the same time, the chapters intend to demonstratethe connections of electrochemistry to areas in addition to chemistry and physics,such as chemical engineering, quantum mechanics, chemical physics, surface sci-ence, biochemistry, and biology, and thereby bring together a vast range of literaturethat covers each topic. While the title of each volume informs of the specific concen-tration chosen by the volume editors and chapter authors, the integral outcome of theseries aims is to offer a broad-based analysis of the total development of the field.

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xii PREFACE TO THE WILEY SERIES ON ELECTROCATALYSIS AND ELECTROCHEMISTRY

The progress of the series will provide a global definition of what electrocatalysis andelectrochemistry are concerned with now and how these fields will evolve overtime.The purpose is twofold; to provide a modern reference for graduate instruction andfor active researchers in the two disciplines, and to document that electrocatalysisand electrochemistry are dynamic fields that are ever-expanding and ever-changingin their scientific profiles.

Creation of each volume required the editor involvement, vision, enthusiasm andtime. The Series Editor thanks all the individual volume editors who graciouslyaccepted the invitations. Special thanks are for Ms. Anita Lekhwani, the SeriesAcquisitions Editor, who extended the invitation to the Series Editor and is a wonderfulhelp in the assembling process of the series.

Andrzej WieckowskiSeries Editor

CONTRIBUTORS

Antolini, Ermete Scuola Scienza Materiali, Via 25 Aprile 22, 16016 Cogoleto(Genova), Italy

Arvia, Alejandro Jorge Instituto de Investigaciones Fisicoquımicas Teoricas y Apli-cadas (INIFTA), Universidad Nacional de La Plata (UNLP), Consejo Nacional deInvestigaciones Cientıficas y Tecnologicas (CONICET), Diagonal 113 y Calle 64,CC16, Suc. 4, 1900 La Plata, Argentina

Baltruschat, Helmut Abteilung Elektrochemie, Universitat Bonn, Romerstr. 164,D-53117 Bonn, Germany

Beltramo, Guillermo Julich Forschungzentrum, Institute of Complex Systems,D-52425 Julich, Germany

Bogolowski, Nicky Abteilung Elektrochemie, Universitat Bonn, Romerstr. 164,D-53117 Bonn, Germany

Bolzan, Agustın Eduardo Instituto de Investigaciones Fisicoquımicas Teoricas yAplicadas (INIFTA), Universidad Nacional de La Plata (UNLP), Consejo Nacionalde Investigaciones Cientıficas y Tecnologicas (CONICET), Diagonal 113 y Calle64, CC16, Suc. 4, 1900 La Plata, Argentina

Calatayud, Monica UPMC Univ Paris 06, UMR 7616, Laboratoire de ChimieTheorique, F-75005, Paris, France; CNRS, UMR 7616, Laboratoire de ChimieTheorique, F-75005, Paris, France

Climent, Vıctor Instituto de Electroquımica, Universidad de Alicante, Apdo. 99,E-03080 Alicante, Spain

Cuesta, Angel Instituto de Quımica Fısica “Rocasolano,” CSIC, C. Serrano, 119,E-28006 Madrid, Spain

Ernst, Siegfried Abteilung Elektrochemie, Universitat Bonn, Romerstr.164, D-53117 Bonn, Germany

Feliu, Juan M. Instituto de Electroquımica, Universidad de Alicante, Apdo. 99,E-03080 Alicante, Spain

Giesen, Margret Julich Forschungzentrum, Institute of Complex Systems, D-52425Julich, Germany

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