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Presel F, Kern CS, Boné TG, Schwarz F, Puschnig P, Ramsey MG, Sterrer M. Charge and adsorption height dependence of the self-metalation of porphyrins on ultrathin MgO(001) films. Phys Chem Chem Phys 2022; 24:28540-28547. [PMID: 36411984 PMCID: PMC9710497 DOI: 10.1039/d2cp04688a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 11/16/2022] [Indexed: 12/07/2023]
Abstract
We have experimentally determined the adsorption structure, charge state, and metalation state of porphin, the fundamental building block of porphyrins, on ultrathin Ag(001)-supported MgO(001) films by scanning tunneling microscopy and photoemission spectroscopy, supported by calculations based on density functional theory. By tuning the substrate work function to values below and above the critical work function for charging, we succeeded in the preparation of 2H-P monolayers which contain negatively charged and uncharged molecules. It is shown that the porphin molecules self-metalate at room temperature, forming the corresponding Mg-porphin, irrespective of their charge state. This is in contrast to self-metalation of tetraphenyl porphyrin (TPP), which occurs on planar MgO(001) only if the molecules are negatively charged. The different reactivity is explained by the reduced molecule-substrate distance of the planar porphin molecule compared to the bulkier TPP. The results of this study shed light on the mechanism of porphyrin self-metalation on oxides and highlight the role of the adsorption geometry on the chemical reactivity.
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Affiliation(s)
- Francesco Presel
- Institute of Physics, University of Graz, NAWI Graz, Universitätsplatz 5, A-8010 Graz, Austria.
| | - Christian S Kern
- Institute of Physics, University of Graz, NAWI Graz, Universitätsplatz 5, A-8010 Graz, Austria.
| | - Thomas G Boné
- Institute of Physics, University of Graz, NAWI Graz, Universitätsplatz 5, A-8010 Graz, Austria.
| | - Florian Schwarz
- Institute of Physics, University of Graz, NAWI Graz, Universitätsplatz 5, A-8010 Graz, Austria.
| | - Peter Puschnig
- Institute of Physics, University of Graz, NAWI Graz, Universitätsplatz 5, A-8010 Graz, Austria.
| | - Michael G Ramsey
- Institute of Physics, University of Graz, NAWI Graz, Universitätsplatz 5, A-8010 Graz, Austria.
| | - Martin Sterrer
- Institute of Physics, University of Graz, NAWI Graz, Universitätsplatz 5, A-8010 Graz, Austria.
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2
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Wechsler D, Fernández CC, Köbl J, Augustin LM, Stumm C, Jux N, Steinrück HP, Williams FJ, Lytken O. Wet-Chemically Prepared Porphyrin Layers on Rutile TiO 2(110). Molecules 2021; 26:molecules26102871. [PMID: 34066129 PMCID: PMC8150575 DOI: 10.3390/molecules26102871] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 05/07/2021] [Accepted: 05/07/2021] [Indexed: 11/16/2022] Open
Abstract
Porphyrins are large organic molecules that are interesting for different applications, such as photovoltaic cells, gas sensors, or in catalysis. For many of these applications, the interactions between adsorbed molecules and surfaces play a crucial role. Studies of porphyrins on surfaces typically fall into one of two groups: (1) evaporation onto well-defined single-crystal surfaces under well-controlled ultrahigh vacuum conditions or (2) more application-oriented wet chemical deposition onto less well-defined high surface area surfaces under ambient conditions. In this study, we will investigate the wet chemical deposition of 5-(monocarboxyphenyl)-10,15,20-triphenylporphyrin (MCTPP) on well-defined rutile TiO2(110) single crystals under ambient conditions. Prior to deposition, the TiO2(110) crystals were also cleaned wet-chemically under ambient conditions, meaning none of the preparation steps were done in ultrahigh vacuum. However, after each preparation step, the surfaces were characterized in ultrahigh vacuum with X-ray photoelectron spectroscopy (XPS) and the result was compared with porphyrin layers prepared in ultrahigh vacuum (UHV) by evaporation. The differences of both preparations when exposed to zinc ion solutions will also be discussed.
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Affiliation(s)
- Daniel Wechsler
- Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Germany; (D.W.); (J.K.); (L.-M.A.); (H.-P.S.)
| | - Cynthia Carolina Fernández
- Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, INQUIMAE-CONICET, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, Buenos Aires C1428EHA, Argentina; (C.C.F.); (F.J.W.)
| | - Julia Köbl
- Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Germany; (D.W.); (J.K.); (L.-M.A.); (H.-P.S.)
| | - Lisa-Marie Augustin
- Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Germany; (D.W.); (J.K.); (L.-M.A.); (H.-P.S.)
| | - Corinna Stumm
- Lehrstuhl für Katalytische Grenzflächenforschung, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Germany;
| | - Norbert Jux
- Lehrstuhl für Organische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Nikolaus-Fiebiger-Str. 10, 91058 Erlangen, Germany;
| | - Hans-Peter Steinrück
- Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Germany; (D.W.); (J.K.); (L.-M.A.); (H.-P.S.)
| | - Federico José Williams
- Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, INQUIMAE-CONICET, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, Buenos Aires C1428EHA, Argentina; (C.C.F.); (F.J.W.)
| | - Ole Lytken
- Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Germany; (D.W.); (J.K.); (L.-M.A.); (H.-P.S.)
- Correspondence:
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3
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Kataev E, Wechsler D, Williams FJ, Köbl J, Tsud N, Franchi S, Steinrück H, Lytken O. Probing the Roughness of Porphyrin Thin Films with X-ray Photoelectron Spectroscopy. Chemphyschem 2020; 21:2293-2300. [PMID: 32820833 PMCID: PMC7702074 DOI: 10.1002/cphc.202000568] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 08/06/2020] [Indexed: 11/08/2022]
Abstract
Thin-film growth of molecular systems is of interest for many applications, such as for instance organic electronics. In this study, we demonstrate how X-ray photoelectron spectroscopy (XPS) can be used to study the growth behavior of such molecular systems. In XPS, coverages are often calculated assuming a uniform thickness across a surface. This results in an error for rough films, and the magnitude of this error depends on the kinetic energy of the photoelectrons analyzed. We have used this kinetic-energy dependency to estimate the roughnesses of thin porphyrin films grown on rutile TiO2 (110). We used two different molecules: cobalt (II) monocarboxyphenyl-10,15,20-triphenylporphyrin (CoMCTPP), with carboxylic-acid anchor groups, and cobalt (II) tetraphenylporphyrin (CoTPP), without anchor groups. We find CoMCTPP to grow as rough films at room temperature across the studied coverage range, whereas for CoTPP the first two layers remain smooth and even; depositing additional CoTPP results in rough films. Although, XPS is not a common technique for measuring roughness, it is fast and provides information of both roughness and thickness in one measurement.
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Affiliation(s)
- Elmar Kataev
- Department of Chemistry and PharmacyFriedrich-Alexander Universität Erlangen-NürnbergEgerlandstraße 3Erlangen91058Germany
| | - Daniel Wechsler
- Department of Chemistry and PharmacyFriedrich-Alexander Universität Erlangen-NürnbergEgerlandstraße 3Erlangen91058Germany
| | - Federico J. Williams
- Departamento de Química Inorgánica, Analítica y Química FísicaUniversidad de Buenos AiresPabellón 2Buenos AiresC1428EHAArgentina
| | - Julia Köbl
- Department of Chemistry and PharmacyFriedrich-Alexander Universität Erlangen-NürnbergEgerlandstraße 3Erlangen91058Germany
| | - Natalia Tsud
- Department of Surface and Plasma ScienceCharles UniversityV Holešovičkách 2Prague11636Czech Republic
| | - Stefano Franchi
- Istituto di Struttura della MateriaConsiglio Nazionale delle Ricerchevia Fosso del Cavaliere100RomaItaly
| | - Hans‐Peter Steinrück
- Department of Chemistry and PharmacyFriedrich-Alexander Universität Erlangen-NürnbergEgerlandstraße 3Erlangen91058Germany
| | - Ole Lytken
- Department of Chemistry and PharmacyFriedrich-Alexander Universität Erlangen-NürnbergEgerlandstraße 3Erlangen91058Germany
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Xiang F, Schmitt T, Raschmann M, Schneider MA. Adsorption and self-assembly of porphyrins on ultrathin CoO films on Ir(100). BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2020; 11:1516-1524. [PMID: 33094085 PMCID: PMC7554680 DOI: 10.3762/bjnano.11.134] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 09/22/2020] [Indexed: 06/11/2023]
Abstract
Porphyrins represent a versatile class of molecules, the adsorption behavior of which on solid surfaces is of fundamental interest due to a variety of potential applications. We investigate here the molecule-molecule and molecule-substrate interaction of Co-5,15-diphenylporphyrin (Co-DPP) and 2H-tetrakis(p-cyanophenyl)porphyrin (2H-TCNP) on one bilayer (1BL) and two bilayer (2BL) thick cobalt oxide films on Ir(100) by scanning tunneling microscopy (STM) and density functional theory (DFT). The two substrates differ greatly with respect to their structural and potential-energy landscape corrugation with immediate consequences for adsorption and self-assembly of the molecules studied. On both films, an effective electronic decoupling from the metal substrate is achieved. However, on the 1BL film, Co-DPP molecules are sufficiently mobile at 300 K and coalesce to self-assembled molecular islands when cooled to 80 K despite their rather weak intermolecular interaction. In contrast, on the 2BL film, due to the rather flat potential landscape, molecular rotation is thermally activated, which effectively prevents self-assembly. The situation is different for 2H-TCNPP, which, due to the additional functional anchoring groups, does not self-assemble on the 1BL film but forms self-assembled compact islands on the 2BL film. The findings demonstrate the guiding effect of the cobalt oxide films of different thickness and the effect of functional surface anchoring.
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Affiliation(s)
- Feifei Xiang
- Solid State Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany
| | - Tobias Schmitt
- Solid State Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany
| | - Marco Raschmann
- Solid State Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany
| | - M Alexander Schneider
- Solid State Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany
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5
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Wähler T, Schuster R, Libuda J. Self-Metalation of Anchored Porphyrins on Atomically Defined Cobalt Oxide Surfaces: In situ Studies by Surface Vibrational Spectroscopy. Chemistry 2020; 26:12445-12453. [PMID: 32333716 PMCID: PMC7590103 DOI: 10.1002/chem.202001331] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Indexed: 12/20/2022]
Abstract
Metalation of anchored porphyrins is essential for their functionality at hybrid interfaces. In this work, we have studied the anchoring and metalation of a functionalized porphyrin derivative, 5-(4-carboxyphenyl)-10,15,20-triphenylporphyrin (MCTPP), on an atomically-defined CoO(100) film under ultrahigh vacuum (UHV) conditions. We follow both the anchoring to the oxide surface and the self-metalation by surface Co2+ ions via infrared reflection absorption spectroscopy (IRAS). At 150 K, MCTPP multilayer films adsorb molecularly on CoO(100) without anchoring to the surface. Upon heating to 195 K, the first layer of porphyrin molecules anchors via formation of a bridging surface carboxylate. Above 460 K, the MCTPP multilayer desorbs and only the anchored monolayer resides on the surface up to temperatures of 600 K approximately. The orientation of anchored MCTPP depends on the surface coverage. At low coverage, the MCTPP adopts a nearly flat-lying geometry, whereas an upright standing film is formed near the multilayer coverage. Self-metalation of MCTPP depends critically on the surface temperature, the coverage and on the molecular orientation. At 150 K, metalation is largely suppressed, while the degree of metalation increases with increasing temperature and reaches a value of around 60 % in the first monolayer at 450 K. At lower coverage higher metalation fractions (85 % and above) are observed, similar as for increasing temperature.
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Affiliation(s)
- Tobias Wähler
- Interface Research and CatalysisErlangen Center for Interface Research and Catalysis (ECRC)Friedrich-Alexander-Universität Erlangen-NürnbergEgerlandstraße 391058ErlangenGermany
| | - Ralf Schuster
- Interface Research and CatalysisErlangen Center for Interface Research and Catalysis (ECRC)Friedrich-Alexander-Universität Erlangen-NürnbergEgerlandstraße 391058ErlangenGermany
| | - Jörg Libuda
- Interface Research and CatalysisErlangen Center for Interface Research and Catalysis (ECRC)Friedrich-Alexander-Universität Erlangen-NürnbergEgerlandstraße 391058ErlangenGermany
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6
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Bertram M, Schuschke C, Waidhas F, Schwarz M, Hohner C, Montero MA, Brummel O, Libuda J. Molecular anchoring to oxide surfaces in ultrahigh vacuum and in aqueous electrolytes: phosphonic acids on atomically-defined cobalt oxide. Phys Chem Chem Phys 2019; 21:23364-23374. [PMID: 31637373 DOI: 10.1039/c9cp03779a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
In this work, we investigated the interaction of phenylphosphonic acid (PPA, C6H5PO3H2) with atomically-defined Co3O4(111) thin films, grown on Ir(100), under ultrahigh vacuum (UHV) conditions and in the electrochemical environment. In the first step, we employed infrared reflection absorption spectroscopy (IRAS) and followed the formation of a saturated monolayer (380 K) in UHV. We observed that the binding motif changes from a chelating tridentate in the sub-monolayer regime to a chelating bidentate at full monolayer coverages. In the electrochemical environment, we analyzed the interaction of PPA with the same Co3O4(111) surface by electrochemical infrared reflection absorption spectroscopy (EC-IRRAS) (0.3 VRHE-1.3 VRHE). When adsorbed at pH 10 from an ammonia buffered aqueous solution, PPA binds to the surface in form of a fully deprotonated chelating bidentate. With increasing electrode potential, we observed two fully reversible processes. At low buffer concentration, protons are released upon oxidation of surface Co2+ ions and lead to protonation of the anchored phosphonates. At high buffer concentration, most of the protons released are accepted by NH3. Simultaneously, the surface phosphonate changes its adsorption motif from bidentate to tridentate while adopting a more upright geometry.
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Affiliation(s)
- Manon Bertram
- Interface Research and Catalysis, Erlangen Catalysis Resource Center, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, D-91058 Erlangen, Germany.
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7
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Wechsler D, Fernández CC, Tariq Q, Tsud N, Prince KC, Williams FJ, Steinrück HP, Lytken O. Interfacial Reactions of Tetraphenylporphyrin with Cobalt-Oxide Thin Films. Chemistry 2019; 25:13197-13201. [PMID: 31403232 DOI: 10.1002/chem.201902680] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 08/08/2019] [Indexed: 11/07/2022]
Abstract
We have studied the adsorption and interfacial reactions of 2H-tetraphenylporphyrin (2HTPP) with cobalt-terminated Co3 O4 (111) and oxygen-terminated CoO(111) thin films using synchrotron-radiation X-ray photoelectron spectroscopy. Already at 275 K, we find evidence for the formation of a metalated species, most likely CoTPP, on both surfaces. The degree of self-metalation increases with temperature on both surfaces until 475 K, where the metalation is almost complete. At 575 K the porphyrin coverage decreases drastically on the reducible cobalt-terminated Co3 O4 (111) surface, while higher temperatures are needed on the non-reducible oxygen-terminated CoO(111). The low temperature self-metalation is similar to that observed on MgO(100) surfaces, but drastically different from that observed on TiO2 (110), where no self-metalation is observed at room temperature.
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Affiliation(s)
- Daniel Wechsler
- Chair of Physical Chemistry II, University Erlangen-Nürnberg, Egerlandstraße 3, 91058, Erlangen, Germany
| | - Cynthia C Fernández
- Departamento de Química Inorgánica, AnalíticayQuímica Física, Facultad de Ciencias ExactasyNaturales, INQUIMAE-CONICET, Universidad de Buenos Aires, Pabellón 2, Buenos Aires, C1428EHA, Argentina
| | - Quratulain Tariq
- Chair of Physical Chemistry II, University Erlangen-Nürnberg, Egerlandstraße 3, 91058, Erlangen, Germany
| | - Nataliya Tsud
- Elettra-Sincrotrone Trieste S.C.p.A., Strada Statale 14, km 163.5, 34149, Basovizza-Trieste, Italy
| | - Kevin C Prince
- Elettra-Sincrotrone Trieste S.C.p.A., Strada Statale 14, km 163.5, 34149, Basovizza-Trieste, Italy.,IOM, Strada Statale 14, km 163.5, 34149, Basovizza-Trieste, Italy
| | - Federico J Williams
- Chair of Physical Chemistry II, University Erlangen-Nürnberg, Egerlandstraße 3, 91058, Erlangen, Germany.,Departamento de Química Inorgánica, AnalíticayQuímica Física, Facultad de Ciencias ExactasyNaturales, INQUIMAE-CONICET, Universidad de Buenos Aires, Pabellón 2, Buenos Aires, C1428EHA, Argentina
| | - Hans-Peter Steinrück
- Chair of Physical Chemistry II, University Erlangen-Nürnberg, Egerlandstraße 3, 91058, Erlangen, Germany
| | - Ole Lytken
- Chair of Physical Chemistry II, University Erlangen-Nürnberg, Egerlandstraße 3, 91058, Erlangen, Germany
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Solar energy storage at an atomically defined organic-oxide hybrid interface. Nat Commun 2019; 10:2384. [PMID: 31160590 PMCID: PMC6546758 DOI: 10.1038/s41467-019-10263-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 05/01/2019] [Indexed: 11/08/2022] Open
Abstract
Molecular photoswitches provide an extremely simple solution for solar energy conversion and storage. To convert stored energy to electricity, however, the photoswitch has to be coupled to a semiconducting electrode. In this work, we report on the assembly of an operational solar-energy-storing organic-oxide hybrid interface, which consists of a tailor-made molecular photoswitch and an atomically-defined semiconducting oxide film. The synthesized norbornadiene derivative 2-cyano-3-(4-carboxyphenyl)norbornadiene (CNBD) was anchored to a well-ordered Co3O4(111) surface by physical vapor deposition in ultrahigh vacuum. Using a photochemical infrared reflection absorption spectroscopy experiment, we demonstrate that the anchored CNBD monolayer remains operational, i.e., can be photo-converted to its energy-rich counterpart 2-cyano-3-(4-carboxyphenyl)quadricyclane (CQC). We show that the activation barrier for energy release remains unaffected by the anchoring reaction and the anchored photoswitch can be charged and discharged with high reversibility. Our atomically-defined solar-energy-storing model interface enables detailed studies of energy conversion processes at organic/oxide hybrid interfaces.
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9
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Yang Y, Tan F, Xie X, Yang X, Zhou Z, Deng K, Huang H. Enhanced Mimetic Enzyme Activity of Phosphorylated Porphyrin Nanocomposite Induced by Localized Surface Plasmon Resonance for Colorimetric Assay. ANAL SCI 2019; 35:691-699. [PMID: 30853695 DOI: 10.2116/analsci.19p004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Plasmon-enhanced light harvesting has been of great interest to enhance the catalytic efficiency of some composites or hybrids. The enhanced peroxidase-like activity of phosphorylated iron(III) porphyrin (TPPFe(III))-based nanocomposite, induced by localized surface plasmon resonance for a colorimetric assay, was developed in this study. Firstly, a phosphate group modification strategy was adopted to synthesize water-soluble iron(III) porphyrin materials. Then, the as-synthesized TPPFe(III) was covalently attached to core-shell gold nanorods (GNRs), GNR@Au2S/AuAgS, to form TPPFe(III)-GNR@Au2S/AuAgS nanocomposite, which shows greatly enhanced peroxidase-like activity compared to TPPFe(III). A mechanism for the enhanced peroxidase-like activity of TPPFe(III)-GNR@Au2S/AuAgS was proposed, which results from a synergic effect of hot electrons excited by localized surface plasmon resonance and photogenerated electrons of the TPPFe(III), verified by experiments. Furthermore, a fast colorimetric assay for the detection of H2O2 and glucose was established based on the unique property of TPPFe(III)-GNR@Au2S/AuAgS. This colorimetric assay was applied to determine practical human serum samples; satisfactory results demonstrate this method has high accuracy. The present study would not only provide some insights into the mechanism of plasmon-activated enzyme-like reactions, but also offer new strategies for improving the catalytic activity of a mimetic enzyme.
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Affiliation(s)
- Yan Yang
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecule, Ministry of Education, Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology
| | - Fang Tan
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecule, Ministry of Education, Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology
| | - Xiaoxue Xie
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecule, Ministry of Education, Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology
| | - Xiumei Yang
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecule, Ministry of Education, Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology
| | - Zaichun Zhou
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecule, Ministry of Education, Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology
| | - Keqin Deng
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecule, Ministry of Education, Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology
| | - Haowen Huang
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecule, Ministry of Education, Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology
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10
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Kollhoff F, Schneider J, Li G, Barkaoui S, Shen W, Berger T, Diwald O, Libuda J. Anchoring of carboxyl-functionalized porphyrins on MgO, TiO 2, and Co 3O 4 nanoparticles. Phys Chem Chem Phys 2018; 20:24858-24868. [PMID: 30230482 DOI: 10.1039/c8cp04873h] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Hybrid materials consisting of functional organic molecules on metal oxide nanomaterials are key components in emerging technologies, for example in energy conversion and molecular electronics. In this work, we present the results of a comparative study of carboxyl-functionalized porphyrins on different oxide nanomaterials. Specifically, we investigated the interaction of 5(3-carboxyphenyl)-10,15,20-triphenyl-21,23H-porphyrin (2H-3-MCTPP) and 5(4-carboxyphenyl)-10,15,20-triphenyl-21,23H-porphyrin (2H-4-MCTPP), on MgO, TiO2, and Co3O4 nanoparticles (NPs) using isothermal and temperature-programmed diffuse reflection infrared Fourier transform spectroscopy (DRIFTS). We show that both porphyrins bind to the NPs, yielding stable monolayer films consisting of tilted surface carboxylates. In all cases, anchoring through the carboxylic acid group suppresses self-metalation of the porphyrin unit. Upon annealing, all anchored porphyrin films undergo metalation. The position of the acid group has no major influence on the reactivity. The same is true for the nature of the metal oxide, suggesting that the observed behaviour is general for most anchored porphyrin films on oxide nanomaterials.
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Affiliation(s)
- Fabian Kollhoff
- Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, D-91058 Erlangen, Germany.
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11
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Kollhoff F, Schneider J, Berger T, Diwald O, Libuda J. Thermally Activated Self-metalation of Carboxy-functionalized Porphyrin Films on MgO Nanocubes. Chemphyschem 2018; 19:2272-2280. [PMID: 29790269 DOI: 10.1002/cphc.201800152] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Indexed: 11/11/2022]
Abstract
We investigated the adsorption of different free-base carboxyl-functionalized porphyrins, 5,10,15,20-tetrakis(4-carboxyphenyl)-21,23H-porphyrin (2H-TCPP) and 5(4-carboxyphenyl)-10,15,20-triphenyl-21,23H-porphyrin (2H-MCTPP), on MgO nanocubes combining IR, UV/Vis and photoluminescence emission spectroscopy. The thermal behavior of the films was monitored in-situ during annealing. Both porphyrins bind to the nanocubes via one and two acid groups respectively, yielding monolayer films consisting of tilted molecules. For 2H-TCPP, two acid groups remain free and give rise to a characteristic IR band. Self-assembly in a tilted adsorbate layer suppresses metalation at room temperature, in contrast to non-functionalized 2H-TPP, which adsorbs flat-lying. Upon heating, 2H-MCTPP undergoes full metalation at temperatures below 280 °C, whereas 2H-TCPP does not metalate at all. The hindered metalation reaction is attributed to the rigidity of the adsorbate film preventing complexation. Our results show that the properties of porphyrin films on oxides can be tuned in a wide range via the position and arrangement of carboxyl anchoring groups.
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Affiliation(s)
- Fabian Kollhoff
- Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, D-, 91058, Erlangen, Germany
| | - Johannes Schneider
- Department of Chemistry and Physics of Materials, Paris Lodron University of Salzburg, Jakob-Haringer-Straße 2a, A-, 5020, Salzburg, Austria
| | - Thomas Berger
- Department of Chemistry and Physics of Materials, Paris Lodron University of Salzburg, Jakob-Haringer-Straße 2a, A-, 5020, Salzburg, Austria
| | - Oliver Diwald
- Department of Chemistry and Physics of Materials, Paris Lodron University of Salzburg, Jakob-Haringer-Straße 2a, A-, 5020, Salzburg, Austria
| | - Jörg Libuda
- Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, D-, 91058, Erlangen, Germany.,Erlangen Catalysis Resource Center and Interdisciplinary Center for Interface-Controlled Processes, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, D-, 91058, Erlangen, Germany
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12
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Schuschke C, Schwarz M, Hohner C, Silva TN, Fromm L, Döpper T, Görling A, Libuda J. Phosphonic Acids on an Atomically Defined Oxide Surface: The Binding Motif Changes with Surface Coverage. J Phys Chem Lett 2018; 9:1937-1943. [PMID: 29595985 DOI: 10.1021/acs.jpclett.8b00668] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We have studied the anchoring mechanism of a phosphonic acid on an atomically defined oxide surface. Using time-resolved infrared reflection absorption spectroscopy, we investigated the reaction of deuterated phenylphosphonic acid (DPPA, C6H5PO3D2) with an atomically defined Co3O4(111) surface in situ during film growth by physical vapor deposition. We show that the binding motif of the phosphonate anchor group changes as a function of coverage. At low coverage, DPPA binds in the form of a chelating tridentate phosphonate, while a transition to a chelating bidentate occurs close to monolayer saturation coverage. However, the coverage-dependent change in the binding motif is not associated with a major change of the molecular orientation, suggesting that the rigid phosphonate linker always maintains the DPPA in a strongly tilted orientation irrespective of the surface coverage.
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Affiliation(s)
- Christian Schuschke
- Lehrstuhl für Physikalische Chemie II , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 3 , D-91058 Erlangen , Germany
| | - Matthias Schwarz
- Lehrstuhl für Physikalische Chemie II , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 3 , D-91058 Erlangen , Germany
| | - Chantal Hohner
- Lehrstuhl für Physikalische Chemie II , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 3 , D-91058 Erlangen , Germany
| | - Thais N Silva
- Lehrstuhl für Physikalische Chemie II , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 3 , D-91058 Erlangen , Germany
| | - Lukas Fromm
- Lehrstuhl für Theoretische Chemie , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 3 , D-91058 Erlangen , Germany
| | - Tibor Döpper
- Lehrstuhl für Theoretische Chemie , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 3 , D-91058 Erlangen , Germany
| | - Andreas Görling
- Lehrstuhl für Theoretische Chemie , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 3 , D-91058 Erlangen , Germany
- Erlangen Catalysis Resource Center and Interdisciplinary Center for Interface Controlled Processes , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 3 , D-91058 Erlangen , Germany
| | - Jörg Libuda
- Lehrstuhl für Physikalische Chemie II , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 3 , D-91058 Erlangen , Germany
- Erlangen Catalysis Resource Center and Interdisciplinary Center for Interface Controlled Processes , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 3 , D-91058 Erlangen , Germany
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13
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Xu T, Waehler T, Vecchietti J, Bonivardi A, Bauer T, Schwegler J, Schulz PS, Wasserscheid P, Libuda J. Interaction of Ester-Functionalized Ionic Liquids with Atomically-Defined Cobalt Oxides Surfaces: Adsorption, Reaction and Thermal Stability. Chemphyschem 2017; 18:3443-3453. [DOI: 10.1002/cphc.201700843] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 09/11/2017] [Indexed: 01/08/2023]
Affiliation(s)
- Tao Xu
- Lehrstuhl für Physikalische Chemie II; Friedrich-Alexander-Universität Erlangen-Nürnberg; Egerlandstraße 3 91058 Erlangen Germany), Fax: +49 9131 8527308
| | - Tobias Waehler
- Lehrstuhl für Physikalische Chemie II; Friedrich-Alexander-Universität Erlangen-Nürnberg; Egerlandstraße 3 91058 Erlangen Germany), Fax: +49 9131 8527308
| | - Julia Vecchietti
- Instituto de Desarrollo Tecnológico para la Industria Química (INTEC), UNL-CONICET; Güemes 3450 3000 Santa Fe Argentina
| | - Adrian Bonivardi
- Instituto de Desarrollo Tecnológico para la Industria Química (INTEC), UNL-CONICET; Güemes 3450 3000 Santa Fe Argentina
| | - Tanja Bauer
- Lehrstuhl für Physikalische Chemie II; Friedrich-Alexander-Universität Erlangen-Nürnberg; Egerlandstraße 3 91058 Erlangen Germany), Fax: +49 9131 8527308
| | - Johannes Schwegler
- Lehrstuhl für Chemische Reaktionstechnik; Friedrich-Alexander-Universität Erlangen-Nürnberg; Egerlandstrasse 3 91058 Erlangen Germany
| | - Peter S. Schulz
- Lehrstuhl für Chemische Reaktionstechnik; Friedrich-Alexander-Universität Erlangen-Nürnberg; Egerlandstrasse 3 91058 Erlangen Germany
| | - Peter Wasserscheid
- Lehrstuhl für Chemische Reaktionstechnik; Friedrich-Alexander-Universität Erlangen-Nürnberg; Egerlandstrasse 3 91058 Erlangen Germany
| | - Joerg Libuda
- Lehrstuhl für Physikalische Chemie II; Friedrich-Alexander-Universität Erlangen-Nürnberg; Egerlandstraße 3 91058 Erlangen Germany), Fax: +49 9131 8527308
- Erlangen Catalysis Resource Center and Interdisciplinary Center for Interface Controlled Processes; Friedrich-Alexander-Universität Erlangen-Nürnberg; 91058 Erlangen Germany
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14
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Xu T, Waehler T, Vecchietti J, Bonivardi A, Bauer T, Schwegler J, Schulz PS, Wasserscheid P, Libuda J. Gluing Ionic Liquids to Oxide Surfaces: Chemical Anchoring of Functionalized Ionic Liquids by Vapor Deposition onto Cobalt(II) Oxide. Angew Chem Int Ed Engl 2017; 56:9072-9076. [PMID: 28600894 DOI: 10.1002/anie.201704107] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Indexed: 11/05/2022]
Abstract
Ionic liquids (IL) hold a great potential as novel electrolytes for applications in electronic materials and energy technology. The functionality of ILs in these applications relies on their interface to semiconducting nanomaterials. Therefore, methods to control the chemistry and structure of this interface are the key to assemble new IL-based electronic and electrochemical materials. Here, we present a new method to prepare a chemically well-defined interface between an oxide and an IL film. An imidazolium-based IL, which is carrying an ester group, is deposited onto cobalt oxide surface by evaporation. The IL binds covalently to the surface by thermally activated cleavage of the ester group and formation of a bridging carboxylate. The anchoring reaction shows high structure sensitivity, which implies that the IL film can be adhered selectively to specific oxide surfaces.
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Affiliation(s)
- Tao Xu
- Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstrasse 3, 91058, Erlangen, Germany
| | - Tobias Waehler
- Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstrasse 3, 91058, Erlangen, Germany
| | - Julia Vecchietti
- Instituto de Desarrollo Tecnológico para la Industria Química (INTEC) UNL-CONICET, Güemes 3450, 3000, Santa Fe, Argentina
| | - Adrian Bonivardi
- Instituto de Desarrollo Tecnológico para la Industria Química (INTEC) UNL-CONICET, Güemes 3450, 3000, Santa Fe, Argentina
| | - Tanja Bauer
- Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstrasse 3, 91058, Erlangen, Germany
| | - Johannes Schwegler
- Lehrstuhl für Chemische Reaktionstechnik, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstrasse 3, 91058, Erlangen, Germany
| | - Peter S Schulz
- Lehrstuhl für Chemische Reaktionstechnik, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstrasse 3, 91058, Erlangen, Germany
| | - Peter Wasserscheid
- Lehrstuhl für Chemische Reaktionstechnik, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstrasse 3, 91058, Erlangen, Germany
| | - Joerg Libuda
- Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstrasse 3, 91058, Erlangen, Germany.,Erlangen Catalysis Resource Center and Interdisciplinary Center Interface Controlled Processes, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058, Erlangen, Germany
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15
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Xu T, Waehler T, Vecchietti J, Bonivardi A, Bauer T, Schwegler J, Schulz PS, Wasserscheid P, Libuda J. Gluing Ionic Liquids to Oxide Surfaces: Chemical Anchoring of Functionalized Ionic Liquids by Vapor Deposition onto Cobalt(II) Oxide. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201704107] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Tao Xu
- Lehrstuhl für Physikalische Chemie II; Friedrich-Alexander-Universität Erlangen-Nürnberg; Egerlandstrasse 3 91058 Erlangen Germany
| | - Tobias Waehler
- Lehrstuhl für Physikalische Chemie II; Friedrich-Alexander-Universität Erlangen-Nürnberg; Egerlandstrasse 3 91058 Erlangen Germany
| | - Julia Vecchietti
- Instituto de Desarrollo Tecnológico para la Industria Química (INTEC) UNL-CONICET; Güemes 3450 3000 Santa Fe Argentina
| | - Adrian Bonivardi
- Instituto de Desarrollo Tecnológico para la Industria Química (INTEC) UNL-CONICET; Güemes 3450 3000 Santa Fe Argentina
| | - Tanja Bauer
- Lehrstuhl für Physikalische Chemie II; Friedrich-Alexander-Universität Erlangen-Nürnberg; Egerlandstrasse 3 91058 Erlangen Germany
| | - Johannes Schwegler
- Lehrstuhl für Chemische Reaktionstechnik; Friedrich-Alexander-Universität Erlangen-Nürnberg; Egerlandstrasse 3 91058 Erlangen Germany
| | - Peter S. Schulz
- Lehrstuhl für Chemische Reaktionstechnik; Friedrich-Alexander-Universität Erlangen-Nürnberg; Egerlandstrasse 3 91058 Erlangen Germany
| | - Peter Wasserscheid
- Lehrstuhl für Chemische Reaktionstechnik; Friedrich-Alexander-Universität Erlangen-Nürnberg; Egerlandstrasse 3 91058 Erlangen Germany
| | - Joerg Libuda
- Lehrstuhl für Physikalische Chemie II; Friedrich-Alexander-Universität Erlangen-Nürnberg; Egerlandstrasse 3 91058 Erlangen Germany
- Erlangen Catalysis Resource Center and Interdisciplinary Center Interface Controlled Processes; Friedrich-Alexander-Universität Erlangen-Nürnberg; 91058 Erlangen Germany
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16
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Mohr S, Schmitt T, Döpper T, Xiang F, Schwarz M, Görling A, Schneider MA, Libuda J. Coverage-Dependent Anchoring of 4,4'-Biphenyl Dicarboxylic Acid to CoO(111) Thin Films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:4178-4188. [PMID: 28402643 DOI: 10.1021/acs.langmuir.7b00465] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We investigated the adsorption behavior of 4,4'-biphenhyl dicarboxylic acid (BDA) on well-ordered CoO(111) films grown on Ir(100) as a function of coverage and temperature using time-resolved and temperature-programmed infrared reflection absorption spectroscopy (TR-IRAS, TP-IRAS) in combination with density functional theory (DFT) and scanning tunneling microscopy (STM) under ultrahigh vacuum (UHV) conditions. To compare the binding behavior of BDA as a function of the oxide film thickness, three different CoO(111) film thicknesses were explored: films of about 20 bilayers (BLs) (approximately 5 nm), 2 BLs, and 1 BL. The two carboxylic acid groups of BDA offer two potential anchoring points to the oxide surface. At 150 K, intact BDA adsorbs on 20 BL thick oxide films in planar geometry with the phenyl rings aligned parallel to the surface. With decreasing oxide film thickness, we observe an increasing tendency for deprotonation and the formation of flat-lying BDA molecules anchored as dicarboxylates. After saturation of the first monolayer, intact BDA multilayers grow with molecules aligned parallel to the surface. The BDA multilayer desorbs at around 360 K. Completely different growth behavior is observed if BDA is deposited above the multilayer desorption temperature. Initially, doubly deprotonated dicarboxylates are formed by adopting a flat-lying orientation. With increasing exposure, however, the adsorbate layer transforms into upright standing monocarboxylates. A sharp OH stretching band (3584 cm-1) and a blue-shifted CO stretching band (1759 cm-1) indicate weakly interacting apical carboxylic acid groups at the vacuum interface. The anchored monocarboxylate phase slowly desorbs in a temperature range of up to 470 K. At higher temperature, a flat-lying doubly deprotonated BDA is formed, which desorbs and decomposes in a temperature range of up to 600 K.
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Affiliation(s)
- Susanne Mohr
- Lehrstuhl für Physikalische Chemie II, ‡Lehrstuhl für Festkörperphysik, §Lehrstuhl für Theoretische Chemie, and ∥Erlangen Catalysis Resource Center and Interdisciplinary Center Interface-Controlled Processes, Friedrich-Alexander-Universität Erlangen-Nürnberg , 91058 Erlangen, Germany
| | - Tobias Schmitt
- Lehrstuhl für Physikalische Chemie II, ‡Lehrstuhl für Festkörperphysik, §Lehrstuhl für Theoretische Chemie, and ∥Erlangen Catalysis Resource Center and Interdisciplinary Center Interface-Controlled Processes, Friedrich-Alexander-Universität Erlangen-Nürnberg , 91058 Erlangen, Germany
| | - Tibor Döpper
- Lehrstuhl für Physikalische Chemie II, ‡Lehrstuhl für Festkörperphysik, §Lehrstuhl für Theoretische Chemie, and ∥Erlangen Catalysis Resource Center and Interdisciplinary Center Interface-Controlled Processes, Friedrich-Alexander-Universität Erlangen-Nürnberg , 91058 Erlangen, Germany
| | - Feifei Xiang
- Lehrstuhl für Physikalische Chemie II, ‡Lehrstuhl für Festkörperphysik, §Lehrstuhl für Theoretische Chemie, and ∥Erlangen Catalysis Resource Center and Interdisciplinary Center Interface-Controlled Processes, Friedrich-Alexander-Universität Erlangen-Nürnberg , 91058 Erlangen, Germany
| | - Matthias Schwarz
- Lehrstuhl für Physikalische Chemie II, ‡Lehrstuhl für Festkörperphysik, §Lehrstuhl für Theoretische Chemie, and ∥Erlangen Catalysis Resource Center and Interdisciplinary Center Interface-Controlled Processes, Friedrich-Alexander-Universität Erlangen-Nürnberg , 91058 Erlangen, Germany
| | - Andreas Görling
- Lehrstuhl für Physikalische Chemie II, ‡Lehrstuhl für Festkörperphysik, §Lehrstuhl für Theoretische Chemie, and ∥Erlangen Catalysis Resource Center and Interdisciplinary Center Interface-Controlled Processes, Friedrich-Alexander-Universität Erlangen-Nürnberg , 91058 Erlangen, Germany
| | - M Alexander Schneider
- Lehrstuhl für Physikalische Chemie II, ‡Lehrstuhl für Festkörperphysik, §Lehrstuhl für Theoretische Chemie, and ∥Erlangen Catalysis Resource Center and Interdisciplinary Center Interface-Controlled Processes, Friedrich-Alexander-Universität Erlangen-Nürnberg , 91058 Erlangen, Germany
| | - Jörg Libuda
- Lehrstuhl für Physikalische Chemie II, ‡Lehrstuhl für Festkörperphysik, §Lehrstuhl für Theoretische Chemie, and ∥Erlangen Catalysis Resource Center and Interdisciplinary Center Interface-Controlled Processes, Friedrich-Alexander-Universität Erlangen-Nürnberg , 91058 Erlangen, Germany
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