Comment pubs.acs.org/JPCC
Reply to “Comment on ‘Using Photoelectron Spectroscopy and Quantum Mechanics to Determine d‑Band Energies of Metals for Catalytic Applications’” Timo Hofmann,*,†,‡ Ted H. Yu,§ Michael Folse,† Lothar Weinhardt,†,∥,⊥,# Marcus Bar̈ ,†,¶,▽ Yufeng Zhang,†,○ Boris V. Merinov,§ Deborah J. Myers,◊ William A. Goddard, III,§ and Clemens Heske*,†,⊥,#,+ †
Department of Chemistry, University of Nevada, Las Vegas (UNLV), 4505 South Maryland Parkway, Las Vegas, Nevada 89154-4003, United States ‡ Bundeswehr Research Institute for Materials, Fuels and Lubricants (WIWeB), Institutsweg 1, 85435 Erding, Germany § Materials and Process Simulation Center, m/c 139-74, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States ∥ Experimentelle Physik VII, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany ⊥ Institute for Photon Science and Synchrotron Radiation, Karlsruhe Institute of Technology (KIT), Hermann-v.-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany # ANKA Synchrotron Radiation Facility, Karlsruhe Institute of Technology (KIT), Hermann-v.-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany ¶ Solar Energy Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, D-14109 Berlin, Germany ▽ Institut für Physik und Chemie, Brandenburgische Technische Universität Cottbus, Konrad-Wachsmann-Allee 1, D-03046 Cottbus, Germany ○ Department of Physics, Xiamen University, 422 Si-Ming-Nan-Lu, Xiamen, Fujian, 361005, People’s Republic of China ◊ Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, United States + Institute for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology (KIT), Engesserstr. 18/20, 76128 Karlsruhe, Germany
J. Phys. Chem. C 2012, 116 (45), 24016−24026. DOI: 10.1021/jp303276z J. Phys. Chem. C 2013, 117. DOI: 10.1021/jp312595p
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then allows a symmetry-resolved analysis) and rather asserts that we “attempt to correlate reactivity trends with d-band centers for a broad variety of metals”. Such a correlation is not feasible, as the authors of the comment and our paper point out. Indeed, metals of very different electronic structure character (described in the comment as “the matrix element”) will behave very differently, and a simple averaging of the dband is unlikely to describe the complex situation adequately. Nevertheless, the simplified model is used frequently within the community (e.g., refs 1 and 2), also for very different metals, and hence it is important to point out such shortcomings.
e wholeheartedly agree with the majority of statements made in the commentthat an understanding of the electronic structure of catalyst surfaces to understand their catalytic activity is one of the most important subjects within the field of catalysis research, that a simplified approach to correlating electronic structure and activity would be desirable, that our study testing, among other things, such a correlation is therefore of “significant importance”, that, however, such a simplified correlation is not at all straightforward, and hence an oversimplified “d-band center model” is not really adequate to describe the complicated processes involved in catalytic activity. The comment also gives a nice example of final state effects in photoemission spectra (a satellite structure 6 eV below the Fermi energy of Fe, Co, and Ni), which obscure an experimental determination of the ground state d-band center (as described in our paper). Finally, the comment gives a good summary of the bibliography of the comment’s authors in this research field. The comment, however, fails to recognize the two main goals of our paper (namely, a thorough analysis of various photoelectron spectroscopy approaches and a novel concept to optimize the energy scale of associated density functional calculations using the optimized experimental results, which © XXXX American Chemical Society
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AUTHOR INFORMATION
Corresponding Author
*E-mail:
[email protected];
[email protected]. Notes
The authors declare no competing financial interest. Received: February 15, 2013 Revised: February 27, 2013
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dx.doi.org/10.1021/jp401620e | J. Phys. Chem. C XXXX, XXX, XXX−XXX
The Journal of Physical Chemistry C
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Comment
REFERENCES
(1) Lima, F. H. B.; Zhang, J.; Shao, M. H.; Sasaki, K.; Vukmirovic, M. B.; Ticianelli, E. A.; Adzic, R. R. Catalytic Activity−d-Band Center Correlation for the O2 Reduction Reaction on Platinum in Alkaline Solutions. J. Phys. Chem. C 2007, 111, 404−410. (2) Tamura, M.; Kon, K.; Satsuma, A.; Shimizu, K. Volcano-Curves for Dehydrogenation of 2-Propanol and Hydrogenation of Nitrobenzene by SiO2-Supported Metal Nanoparticles Catalysts As Described in Terms of a d-Band Model. ACS Catal. 2012, 2, 1904− 1909.
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dx.doi.org/10.1021/jp401620e | J. Phys. Chem. C XXXX, XXX, XXX−XXX
