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The Electron Factor in Catalysis on Metals Electrocatalysis on Non-Metallic Surfaces

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NBSIR 7^^-1049 The Electron Factor in Catalysis on Metals Electrocatalysis on Non-Metallic Surfaces L. H. Bennett and A. D. Franklin Institute for Materials Research National Bureau of Standards Washington, D. C. 20234 May, 1976 Summary Report Prepared for Division of Materials Research National Science Foundation Division of Conservation Research and Technology Energy Research and Development Administration NBSIR 75-1049 THE ELECTRON FACTOR IN CATALYSIS ON METALS ELECTROCATALYSIS ON NON-METALLIC SURFACES L. H. Bennett and A. D. Franklin Institute for Materials Research National Bureau of Standards Washington, D. C. 20234 May, 1976 Summary Report Prepared for Division of Materials Research National Science Foundation Division of Conservation Research and Technology Energy Research and Development Administration U.S. DEPARTMENT OF COMMERCE, Elliot L. Richardson, Secretary Dr. Betsy Ancker-Johnson, Assistant Secretary for Science and Techno/ogy NATIONAL BUREAU OF STANDARDS. Ernest Ambler, Acting Director : Energy Workshops The Electron Factor In Catalysis On Metals Electrocatalysis On Non-Metallic Surfaces (December 8-12, 1975, Gaithersburg, MD) L. H. Bennett and A. D. Franklin Institute for Materials Research National Bureau of Standards Gaithersburg, MD 20760 May , 1976 Summary Report ared for: Division of Materials Research, National Science Foundation Division of Conservation Research and Technology, Energy Research and Development Administration Table of Contents 1. THE ELECTRON FACTOR IN CATALYSIS ON METALS 1 1.1 Overview of the Workshop 1 1.2 Attendance List ' 3 1.3 Outline of Workshop 9 1.3.1 Format 9 1.3.2 Panel on Experimental Techniques 9 1.3.3 Panel on Effects of Alloying 9 1.3.4 Panel on Geometrical Effects 10 1.3.5 Panel on Electronic Structure 10 1.3.6 Proceedings 10 1.4 Summary of Discussions 11 1.4.1 Experimental Techniques 11 1.4.2 Effects of Alloying 12 1.4.3 Geometrical Effects 12 1.4.4 Electronic Structure 13 2. ELECTROCATALYSIS ON NON-METALLIC SURFACES 14 2 . 1 Overview of the Workshop 14 2.2 Steering Committee 22 2.3 Attendance List 23 2.4 Program and Abstracts 28 2.4.1 Session 1 - Joint Session with Workshop on the Electron Factor in Catalysis on Metals 28 2.4.2 Session 2 - Theory of Electrocatalysis on Non-Metallic Surfaces 29 2.4.3 Session 3 - Characterization of Non-Metallic Electrocatalytic Surfaces 34 Session 4 - Electrochemical Processes on Non-Metallic Surfaces I . Session 5 - Electrochemical Processes on Non-Metallic Surfaces II Session 6 - Electrochemical Processes on Non-Metallic Surfaces III Session 7 - Electrochemistry at Solid Electrolyte Interfaces, etc. ...... Session 8 - Panel Report and Discussion 1 1. THE ELECTRON FACTOR IN CATALYSIS ON METALS 1.1 Overview of the Workshop Traditionally, the term electron factor in catalysis has denoted a relationship between catalytic activity and the bulk electronic struc- ture of the catalyst. While there is abundant empirical evidence of the importance of the electron factor in heterogeneous catalysis, its precise definition and relation to other factors, particularly the geometric factor, have yet to be established. The interdependence of electronic and geometric factors in bulk bonding is well known: examples include the Hume-Rothery rules of alloy phase stability, relating valence, size, and electronegativity; and Pauling's famous equation relating bond length to bond strength. Chemical processes at a solid-fluid interface have not, thus far, been similarly systematized. However, many new and powerful techniques for the analysis and characterization of clean surfaces and small particles, and of chemical complexes on such surfaces have been developed in recent years. It was the aim of this workshop to move toward systematic understanding of this problem through inter- disciplinary action. Specific panel topics were: Experimental Techni- ques, the Effects of Alloying, Geometrical Effects, and the Theory of Electronic Structure. The workshop brought together workers in a range of fields including theoretical physicists engaged in band structure and surface calculations, theoretical chemists doing chemical bonding calculations, surface chem- ists working on clean surfaces and single crystals, practical catalytic chemists engaged in small particle and support effect studies, electro- chemists concerned with activity in aqueous environments, etc. The names and affiliations of all participants are listed in the following section. 2 While progress toward quantitative expression of the Electron Factor in catalysis was limited, this aim served as a focus for the clarification of the capabilities and accomplishments of many experi- mental and computational techniques. The interdisciplinary emphasis of the conference was one of its most fortunate aspects; many of the distinguished experts present found clarification of the relation between their specialties and catalysis. 3 1.2 Attendance List Alayne A. Adams M. Boudart American University Stanford University Dept. of Chemistry Stanford, CA 94305 Massachusetts & Nebraska Ave. , NW Washington, DC 20016 E. 0. Box, Jr. Phillips Petroleum Co. Radoslav Adzic 334A Res. Bldg #1 Institute of Electrochemistry Research Center Karnegieva 4 Bartlesville, OK 74003 Belgrade, Yugoslavia 11001 Manfred W. Breiter A. W. Aldag General Electric Co. University of Oklahoma Corp. Research & Development 202 W. Boyd P.O. Box 8 Norman, OK 73069 Schenectady, NY 12345 Alfred B. Anderson Boris D. Cahan Yale University, Chemistry Dept. Case Western Reserve Univ. 225 Prospect St. 2074 Adelbert Road New Haven, CT 06520 Cleveland, OH 44106 Joseph A. Baglio Julio Calderon GTE Labs Dept. of the Army 40 Silvan Avenue AMXFB-CF Waltham, MA 02154 Ft. Belvoir, VA 22060 Alfonso L. Baldi Patrick J. Call Alloy Surfaces Company RCA Laboratories 100 S. Justison Street Washington Road Wilmington, DE 19899 Princeton, NJ 08540 Ian R. Bartky Robert C. Cargill National Bureau of Standards Physical Elect. Industries, Inc. Matls Bldg. , B354 278 Fairtree Plaza Washington, DC 20234 Severna Park, MD 21146 Lawrence H. Bennett Divna Cipris National Bureau of Standards Allied Chem. Corp., Matls Bldg. , B152 Columbia Road Washington, DC 20234 Morristown, NJ 07960 Harold Berger Paul H. Citrin National Bureau of Standards Bell Laboratories Matls Bldg. , B254 600 Mountain Avenue Washington, DC 20234 Murray Hill, NJ 07974 George Birnbaum William L. Clinton National Bureau of Standards Georgetown University Matls Bldg. , B354 37 & 0 Streets, NW Washington, DC 20234 Washington, DC 20057 t 4 Ernest M. Cohn Henry Ehrenreich 103 G Street, SW Harvard University Apt. B-620 Cambridge, MA 02138 Washington, DC 20024 T. L. Einstein Amos Coleman Dept. of Physics & Astronomy Dept. of the Army University of Maryland AMXFB-CF College Park, MD 20742 Ft. Belvior, VA 22060 Nils E. Erickson Bernard R. Cooper National Bureau of Standards West Virginia University Chem Bldg. B248 Dept. of Physics Washington, DC 20234 Morgantovm, WV 26506 Gerhard Ertl John R. Cuthill Universitat Munchen National Bureau of Standards Sophienstr. 11 Matls Bldg. , B148 8 Munchen 2, W. Germany Washington, DC 20234 Billy J. Evans Victor V. Damiano National Bureau of Standards Franklin Institute Res. Labs Matls Bldg. , B150 20th & Benjamin Franklin Pkwy Washington, DC 20234 Philadelphia, PA 19103 Galen B. Fisher H. L. Davis National Bureau of Standards Solid State Div. Chem Bldg. , B248 Oak Ridge National Lab. Washington, DC 20234 Oak Ridge, TN 31830 Robert Mark Friedman Jean F. Delord Monsanto Company Reed College Mail Zone Q3B 3203 SE Woodstock Blvd. 800 N. Lindbergh Blvd. Portland, OR 97222 St. Louis, MO 63166 Thomas W. DeWitt Yasuo Fukuda National Science Foundation Center of Materials Research 1800 G Street, NW University of MD Washington, DC 20550 College Park, MD 20742 Richard A. Diffenbach J. William Gadzuk ERDA National Bureau of Standards 4800 Forbes Avenue Metrology Bldg., B214 Pittsburgh, PA 14213 Washington, DC 20234 C. B. Duke C. D. Gelatt Xerox Corp. Harvard University 800 Phillips Road, W-114 Pierce Hall Webster, NY 14580 Cambridge, MA 02138 Heinz Gerischer Fritz-Haber-Institute der Max-Planck-Gesellschaf Faradayweg 4-6 1 Berlin 33, W. Germany 5 William L. Gordon Howard S. Jarrett Case Western Reserve Univ. E.I. duPont de Nemours & Co. Dept. of Physics Experimental Station Cleveland, OH 44106 Wilmington, DE 19898 Warren Grobman Leslie H. Jenkins IBM Thomas Watson Res. Ctr. Oak Ridge National Laboratory P.O. Box 218 P.O. Box X Yorktown Heights, NY 10598 Oak Ridge, TN 37830 Laszle Guczi Johann A. Joebstl Worcester Polytechnic Institute Electrochemical Div/Lab 3000 Chem. Eng. Dept. AMXFB-EC, USAMERDC Worcester, MA 01609 Ft. Belvoir, VA 22060 Gary L. Haller Harlan B. Johnson Yale University PPG Industries Dept. of Eng. & Applied Science P.O. Box 31 9 Hillhouse Ave. Rittman, OH 44203 New Haven, CT 06520 James R. Katzer Robert S. Hansen Department of Chemical Engineering Ames Laboratory, USERDA University of Delaware Iowa State University Newark, DE 19711 Ames, lA 50011 Richard D. Kelley D . R . Hamann National Bureau of Standards Bell Labs Chem Bldg. , B248 Murray Hill, NJ 07974 Washington, DC 20234 Victor E. Henrich Chris E. Kuyatt MIT, Lincoln Lab. National Bureau of Standards Wood Street Metrology Bldg., B212 Lexington, MA 02155 Washington, DC 20234 Jan F. Herbst M. G. Lagally National Bureau of Standards University of Wisconsin Metrology Bldg. , B214 1109 Eng. Res. Bldg. Washington, DC 20234 Madison, WI 53706 John D. Hoffman John Lambe National Bureau of Standards Ford Motor Company Matls Bldg. , B364 P.O. Box 2053 Washington, DC 20234 Dearborn, MI 48121 Emanuel Horowitz Lennart Larsson National Bureau of Standards University of Lund, Chem. Ctr. Matls Bldg. , B364 P.O.B. 740 Washington, DC 20234 S-220 07 Lund 7, Sweden 6 Richard V. Lawrence S. R. Montgomery Dept. of the Army W. R. Grace & Co. AMXFB-CF Davison Chem. Div. , Tech. Ctr. Ft. Belvoir, VA 22060 5500 Chemical Road Baltimore, MD 21226 Max Lipsicas Yeshlva University Bruno Morosin Belfer Graduate School of Sci. Sandia Labs 2495 Amsterdam Avenue Albuquerque, NM 87115 New York, NY 10033 S. Roy Morrison Farrel Lytle Stanford Research Institute The Boeing Company Menlo Park, CA 94025 P.O.
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