Complex Model Electrocatalysts for the Selective Transformation of Renewable Fuels

• Applicant: Dr. Olaf Brummel
• Subject Area: Physical Chemistry of Solids and Surfaces, Material Characterisation
• Term: from 2019 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 431733372

• Final Report Year: 2025

Final Report Abstract

The goal of this project was to develop advanced electrocatalysts for the selective oxidation of alcohols, such as ethanol, in alkaline environments. This research is particularly relevant for improving the efficiency of energy storage systems, such as direct alcohol fuel cells. Our studies focused on integrating three key functionalities at the nanoscale: (1) effective alcohol binding, (2) controlled carbon-carbon bond cleavage, and (3) targeted oxidation of ethanol-derived intermediates. To achieve this, we designed atomic-scale model catalysts, including well-ordered oxide films, metal oxide nanoparticles, and metal nanoparticles supported on oxides. A major discovery concerned the crucial role of electronic metal–support interactions (EMSI) in determining catalyst stability and activity. For example, platinum (Pt) and palladium (Pd) deposited on cobalt oxide (Co₃O₄) formed more stable structures. However, the EMSI must be fine-tuned to preserve electrocatalytic activity. Additionally, by introducing bimetallic alloys—such as rhodium (Rh) combined with palladium—we were able to introduce additional functionalities. Another breakthrough was the development of a novel in-situ spectroscopy technique, which enables the characterization of atomically defined model systems under operation conditions. This approach revealed that the oxidation states of catalysts in reaction environments can significantly differ from those measured in conventional ex-situ experiments. These findings contribute to the development of more efficient and stable electrocatalysts. In the long run, similar strategies could be applied to the electrocatalytic conversion of other reactants, further advancing energy conversion and the electrification of chemical processes.

Publications

• Cobalt Oxide-Supported Pt Electrocatalysts: Intimate Correlation between Particle Size, Electronic Metal–Support Interaction and Stability. The Journal of Physical Chemistry Letters, 11(19), 8365-8371.
  Bertram, Manon; Prössl, Carolin; Ronovský, Michal; Knöppel, Julius; Matvija, Peter; Fusek, Lukáš; Skála, Tomáš; Tsud, Nataliya; Kastenmeier, Maximilian; Matolín, Vladimír; Mayrhofer, Karl J. J.; Johánek, Viktor; Mysliveček, Josef; Cherevko, Serhiy; Lykhach, Yaroslava; Brummel, Olaf & Libuda, Jörg
  
• Electrochemically controlled energy release from a norbornadiene-based solar thermal fuel: increasing the reversibility to 99.8% using HOPG as the electrode material. Journal of Materials Chemistry A, 8(31), 15658-15664.
  Waidhas, Fabian; Jevric, Martyn; Bosch, Michael; Yang, Tian; Franz, Evanie; Liu, Zhi; Bachmann, Julien; Moth-Poulsen, Kasper; Brummel, Olaf & Libuda, Jörg
  
• Secondary Alcohols as Rechargeable Electrofuels: Electrooxidation of Isopropyl Alcohol at Pt Electrodes. ACS Catalysis, 10(12), 6831-6842.
  Waidhas, Fabian; Haschke, Sandra; Khanipour, Peyman; Fromm, Lukas; Görling, Andreas; Bachmann, Julien; Katsounaros, Ioannis; Mayrhofer, Karl J. J.; Brummel, Olaf & Libuda, Jörg
  
• Model electrocatalysts for the oxidation of rechargeable electrofuels - carbon supported Pt nanoparticles prepared in UHV. Electrochimica Acta, 389, 138716.
  Stumm, Corinna; Kastenmeier, Maximilian; Waidhas, Fabian; Bertram, Manon; Sandbeck, Daniel J.S.; Bochmann, Sebastian; Mayrhofer, Karl J.J.; Bachmann, Julien; Cherevko, Serhiy; Brummel, Olaf & Libuda, Jörg
  
• Photoconversion of 2-Propanol on Rutile Titania: A Combined Liquid-Phase and Surface Science Study. The Journal of Physical Chemistry C, 125(6), 3355-3367.
  Kräuter, Jessica; Mohrhusen, Lars; Waidhas, Fabian; Brummel, Olaf; Libuda, Jörg & Al-Shamery, Katharina
  
• Reactive interaction of isopropanol with Co3O4(1 1 1) and Pt/Co3O4(1 1 1) model catalysts. Journal of Catalysis, 398, 171-184.
  Hohner, Chantal; Ronovský, Michal; Brummel, Olaf; Skála, Tomáš; Šmíd, Břetislav; Tsud, Nataliya; Vorokhta, Mykhailo; Prince, Kevin C.; Mysliveček, Josef; Johánek, Viktor; Lykhach, Yaroslava & Libuda, Jörg
  
• Reduction of Oxide Layers on Au(111): The Interplay between Reduction Rate, Dissolution, and Restructuring. The Journal of Physical Chemistry C, 125(41), 22698-22704.
  Stumm, Corinna; Grau, Sebastian; Speck, Florian D.; Hilpert, Felix; Briega-Martos, Valentín; Mayrhofer, Karl; Cherevko, Serhiy; Brummel, Olaf & Libuda, Jörg
  
• Selective electrooxidation of 2-propanol on Pt nanoparticles supported on Co3O4: an in-situ study on atomically defined model systems. Journal of Physics D: Applied Physics, 54(16), 164002.
  Yang, Tian; Kastenmeier, Maximilian; Ronovský, Michal; Fusek, Lukáš; Skála, Tomáš; Waidhas, Fabian; Bertram, Manon; Tsud, Nataliya; Matvija, Peter; Prince, Kevin C.; Matolín, Vladimír; Liu, Zhi; Johánek, Viktor; Mysliveček, Josef; Lykhach, Yaroslava; Brummel, Olaf & Libuda, Jörg
  
• Stability of the Pd/Co3O4(111) Model Catalysts in Oxidizing and Humid Environments. The Journal of Physical Chemistry C, 125(5), 2907-2917.
  Schuschke, Christian; Fusek, Lukáš; Uvarov, Vitalii; Vorokhta, Mykhailo; Šmíd, Břetislav; Johánek, Viktor; Lykhach, Yaroslava; Libuda, Jörg; Mysliveček, Josef & Brummel, Olaf
  
• Structural Dynamics of Ultrathin Cobalt Oxide Nanoislands under Potential Control. Advanced Functional Materials, 31(13).
  Stumm, Corinna; Bertram, Manon; Kastenmeier, Maximilian; Speck, Florian D.; Sun, Zhaozong; Rodríguez‐Fernández, Jonathan; Lauritsen, Jeppe V.; Mayrhofer, Karl J. J.; Cherevko, Serhiy; Brummel, Olaf & Libuda, Jörg
  
• A combined rotating disk electrode–surface x-ray diffraction setup for surface structure characterization in electrocatalysis. Review of Scientific Instruments, 93(6).
  Jacobse, Leon; Schuster, Ralf; Pfrommer, Johannes; Deng, Xin; Dolling, Silvan; Weber, Tim; Gutowski, Olof; Dippel, Ann-Christin; Brummel, Olaf; Lykhach, Yaroslava; Over, Herbert; Libuda, Jörg; Vonk, Vedran & Stierle, Andreas
  
• A Versatile Approach to Electrochemical In Situ Ambient-Pressure X-ray Photoelectron Spectroscopy: Application to a Complex Model Catalyst. The Journal of Physical Chemistry Letters, 13(47), 11015-11022.
  Brummel, Olaf; Lykhach, Yaroslava; Ralaiarisoa, Maryline; Berasategui, Matias; Kastenmeier, Maximilian; Fusek, Lukáš; Simanenko, Alexander; Gu, Wenqing; Clark, Pip C. J.; Yivlialin, Rossella; Sear, Michael J.; Mysliveček, Josef; Favaro, Marco; Starr, David E. & Libuda, Jörg
  
• Electrocatalytic Energy Release of Norbornadiene‐Based Molecular Solar Thermal Systems: Tuning the Electrochemical Stability by Molecular Design. ChemSusChem, 15(24).
  Franz, Evanie; Krappmann, Daniel; Fromm, Lukas; Luchs, Tobias; Görling, Andreas; Hirsch, Andreas; Brummel, Olaf & Libuda, Jörg
  
• Electrochemically Triggered Energy Release from an Azothiophene‐Based Molecular Solar Thermal System. ChemSusChem, 15(18).
  Franz, Evanie; Kunz, Anne; Oberhof, Nils; Heindl, Andreas H.; Bertram, Manon; Fusek, Lukas; Taccardi, Nicola; Wasserscheid, Peter; Dreuw, Andreas; Wegner, Hermann A.; Brummel, Olaf & Libuda, Jörg
  
• OperandoIdentification of the Reversible Skin Layer on Co3O4as a Three-Dimensional Reaction Zone for Oxygen Evolution. ACS Catalysis, 12(6), 3256-3268.
  Wiegmann, Tim; Pacheco, Ivan; Reikowski, Finn; Stettner, Jochim; Qiu, Canrong; Bouvier, Mathilde; Bertram, Manon; Faisal, Firas; Brummel, Olaf; Libuda, Jörg; Drnec, Jakub; Allongue, Philippe; Maroun, Fouad & Magnussen, Olaf M.
  
• Particle Size and Shape Effects in Electrochemical Environments: Pd Particles Supported on Ordered Co3O4(111) and Highly Oriented Pyrolytic Graphite. The Journal of Physical Chemistry C, 126(30), 12870-12881.
  Kastenmeier, Maximilian; Fusek, Lukáš; Deng, Xin; Skála, Tomáš; Mehl, Sascha; Tsud, Nataliya; Grau, Sebastian; Stumm, Corinna; Uvarov, Vitalii; Johánek, Viktor; Libuda, Jörg; Lykhach, Yaroslava; Mysliveček, Josef & Brummel, Olaf
  
• Redox-mediated C–C bond scission in alcohols adsorbed on CeO2− x thin films. Journal of Physics: Condensed Matter, 34(19), 194002.
  Lykhach, Yaroslava; Johánek, Viktor; Neitzel, Armin; Skála, Tomáš; Tsud, Nataliya; Beranová, Klára; Mysliveček, Josef; Brummel, Olaf & Libuda, Jörg
  
• The role of defects in the photoconversion of 2-propanol on rutile titania: Operando spectroscopy combined with elementary studies. Journal of Catalysis, 406, 134-144.
  Kräuter, Jessica; Franz, Evanie; Waidhas, Fabian; Brummel, Olaf & Al-Shamery, Katharina
  
• Activity Trends for the Selective Oxidation of 2-Propanol to Acetone on Noble Metal Electrodes in Alkaline Electrolyte. ACS Catalysis, 13(22), 14562-14569.
  Mangoufis-Giasin, Iosif; Fusek, Lukáš; Yang, Tian; Khanipour, Peyman; Brummel, Olaf; Libuda, Jörg; Mayrhofer, Karl J. J.; Calle-Vallejo, Federico & Katsounaros, Ioannis
  
• Au‐Catalyzed Energy Release in a Molecular Solar Thermal (MOST) System: A Combined Liquid‐Phase and Surface Science Study. ChemPhotoChem, 8(1).
  Eschenbacher, Roman; Hemauer, Felix; Franz, Evanie; Leng, Andreas; Schwaab, Valentin; Waleska‐Wellnhofer, Natalie J.; Freiberger, Eva Marie; Fromm, Lukas; Xu, Tao; Görling, Andreas; Hirsch, Andreas; Steinrück, Hans‐Peter; Papp, Christian; Brummel, Olaf & Libuda, Jörg
  
• Chemical and Structural In-Situ Characterization of Model Electrocatalysts by Combined Infrared Spectroscopy and Surface X-ray Diffraction. The Journal of Physical Chemistry Letters, 14(39), 8820-8827.
  Brummel, Olaf; Jacobse, Leon; Simanenko, Alexander; Deng, Xin; Geile, Simon; Gutowski, Olof; Vonk, Vedran; Lykhach, Yaroslava; Stierle, Andreas & Libuda, Jörg
  
• Competition of Acetone Reduction and Hydrogen Evolution on Pt Single Crystal Electrodes in the Absence and Presence of the Ionic Liquid [C2C1Im][OTf]. The Journal of Physical Chemistry C, 127(47), 22975-22983.
  Kastenmeier, Maximilian; Franz, Evanie; Waidhas, Fabian; Yang, Tian; Taccardi, Nicola; Wasserscheid, Peter; Brummel, Olaf & Libuda, Jörg
  
• How Adsorption Affects the Energy Release in an Azothiophene-Based Molecular Solar–Thermal System. The Journal of Physical Chemistry Letters, 14(6), 1470-1477.
  Franz, Evanie; Jung, Jannis; Kunz, Anne; Wegner, Hermann A.; Brummel, Olaf; Mollenhauer, Doreen & Libuda, Jörg
  
• Mechanistic Insight into Solution-Based Atomic Layer Deposition of CuSCN Provided by In Situ and Ex Situ Methods. ACS Applied Materials & Interfaces, 15(15), 19536-19544.
  Hilpert, Felix; Liao, Pei-Chun; Franz, Evanie; Koch, Vanessa M.; Fromm, Lukas; Topraksal, Ece; Görling, Andreas; Smith, Ana-Sunc̆ana; Barr, Maïssa K. S.; Bachmann, Julien; Brummel, Olaf & Libuda, Jörg
  
• Pd/Co3O4(111) Interface Formation. The Journal of Physical Chemistry C, 127(12), 6034-6044.
  Kastenmeier, Maximilian; Fusek, Lukáš; Mohamed, Fatema; Schuschke, Christian; Ronovský, Michal; Skála, Tomáš; Farnesi Camellone, Matteo; Tsud, Nataliya; Johánek, Viktor; Fabris, Stefano; Libuda, Jörg; Piccinin, Simone; Lykhach, Yaroslava; Mysliveček, Josef & Brummel, Olaf
  
• Strong Activity Changes Observable during the First Pretreatment Cycles of Trimetallic PtNiMo/C Catalysts. ChemElectroChem, 10(16).
  Danisman, Bilal; Zhang, Gui‐Rong; Baumunk, Adrian F.; Yang, Juntao; Brummel, Olaf; Darge, Philipp; Mayrhofer, Karl J. J.; Libuda, Jörg; Ledendecker, Marc & Etzold, Bastian J. M.
  
• A model study of ceria–Pt electrocatalysts: stability, redox properties and hydrogen intercalation. Physical Chemistry Chemical Physics, 26(3), 1630-1639.
  Fusek, Lukáš; Samal, Pankaj Kumar; Keresteš, Jiří; Khalakhan, Ivan; Johánek, Viktor; Lykhach, Yaroslava; Libuda, Jörg; Brummel, Olaf & Mysliveček, Josef
  
• Atomistic picture of electronic metal support interaction and the role of water. Journal of Materials Chemistry A, 12(6), 3258-3264.
  Fusek, Lukáš; Farnesi Camellone, Matteo; Ronovský, Michal; Kastenmeier, Maximilian; Skála, Tomáš; Kumar Samal, Pankaj; Tsud, Nataliya; Mehl, Sascha; Škvára, Jan; Dolák, Tomáš; Uvarov, Vitalii; Setvín, Martin; Johánek, Viktor; Fabris, Stefano; Brummel, Olaf; Libuda, Jörg; Mysliveček, Josef; Piccinin, Simone & Lykhach, Yaroslava
  
• Bimetallic Pd–Rh Nanoparticles Supported on Co3O4(111): Atomic Ordering and Stability. The Journal of Physical Chemistry C, 129(1), 983-992.
  Simanenko, Alexander; Škvára, Jan; Samal, Pankaj Kumar; Fusek, Lukáš; Kastenmeier, Maximilian; Ronovský, Michal; Skála, Tomáš; Tsud, Nataliya; Mehl, Sascha; Johánek, Viktor; Mysliveček, Josef; Brummel, Olaf; Lykhach, Yaroslava & Libuda, Jörg
  
• C C bond cleavage in the electrooxidation of 2,3-butanediol controlled by an ionic liquid modifier. Journal of Catalysis, 435, 115541.
  Yang, Juntao; Haßfurther, Florian; Hilpert, Felix; Hussain, Zarah; Yang, Tian; Taccardi, Nicola; Wasserscheid, Peter; Brummel, Olaf & Libuda, Jörg
  
• Increasing Activity of Trimetallic Oxygen Reduction PtNiMo/C Catalysts Through Initial Conditioning. ChemElectroChem, 11(9).
  Danisman, Bilal; Zhang, Gui‐Rong; Baumunk, Adrian F.; Yang, Juntao; Brummel, Olaf; Darge, Philipp; Dworschak, Dominik; Mayrhofer, Karl J. J.; Libuda, Jörg; Zhou, Xin; Wu, Mingjian; Spiecker, Erdmann; Ledendecker, Marc & Etzold, Bastian J. M.
  
• Interactions of the Ionic Liquid [C2C1Im][DCA] with Au(111) Electrodes: Interplay between Ion Adsorption, Electrode Structure, and Stability. The Journal of Physical Chemistry C, 128(7), 2834-2843.
  Yang, Juntao; Hilpert, Felix; Qiu, Yunsheng; Franz, Evanie; Briega-Martos, Valentín; Cherevko, Serhiy; Mayrhofer, Karl; Brummel, Olaf & Libuda, Jörg
  
• Mechanistic Study of Ethanol Decomposition on Co3O4(111) and Pd/Co3O4(111) Model Catalysts. ChemCatChem, 17(5).
  Reindl, Simone; Škvára, Jan; Hauner, Jonas; Simanenko, Alexander; Kastenmeier, Maximilian; Ronovský, Michal; Skála, Tomáš; Tsud, Nataliya; Kettner, Miroslav; Mehl, Sascha; Vorochta, Michael; Šmíd, Břetislav; Retzer, Tanja; Mysliveček, Josef; Brummel, Olaf; Johánek, Viktor; Lykhach, Yaroslava & Libuda, Jörg
  
• Origin of the Low Overpotential for Isopropanol Oxidation on Pt–Ru Electrocatalysts. ACS Energy Letters, 9(10), 4875-4882.
  Simanenko, Alexander; Samal, Pankaj Kumar; Hübsch, Robert; Škvára, Jan; Yang, Juntao; Kastenmeier, Maximilian; Winkler, Florian; Skála, Tomáš; Tsud, Nataliya; Mehl, Sascha; Mysliveček, Josef; Brummel, Olaf; Lykhach, Yaroslava & Libuda, Jörg
  
• Toward High-Energy-Density Fuels for Direct Liquid Organic Hydrogen Carrier Fuel Cells: Electrooxidation of 1-Cyclohexylethanol. The Journal of Physical Chemistry Letters, 15(9), 2529-2536.
  Fusek, Lukáš; Briega-Martos, Valentín; Minichová, Maria; Fromm, Lukas; Franz, Evanie; Yang, Juntao; Görling, Andreas; Mayrhofer, Karl J.J.; Wasserscheid, Peter; Cherevko, Serhiy; Brummel, Olaf & Libuda, Jörg
  
• Be Aware of Transient Dissolution Processes in Co3O4 Acidic Oxygen Evolution Reaction Electrocatalysts. Journal of the American Chemical Society, 147(4), 3517-3528.
  Priamushko, Tatiana; Franz, Evanie; Logar, Anja; Bijelić, Lazar; Guggenberger, Patrick; Escalera-López, Daniel; Zlatar, Matej; Libuda, Jörg; Kleitz, Freddy; Hodnik, Nejc; Brummel, Olaf & Cherevko, Serhiy
  
• The Influence of Ionic Liquid Modification on the Restructuring of Trimetallic PtNiMo/C Catalysts During Conditioning. ChemElectroChem, 12(5).
  Danisman, Bilal; Yang, Juntao; Zhang, Gui‐Rong; Brummel, Olaf; Márton Kovács, Miklós; Dworschak, Dominik; Steffen, Julien; Ledendecker, Marc; Görling, Andreas; Mayrhofer, Karl J. J.; Libuda, Jörg & Etzold, Bastian J. M.