1
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Knoll S, Zens C, Maisuradze T, Schmidt H, Kupfer S, Zedler L, Dietzek-Ivanšić B, Streb C. Light-Induced Charge Separation in Covalently Linked BODIPY-Quinone-Alkyne Dyads. Chemistry 2024; 30:e202303250. [PMID: 38411403 DOI: 10.1002/chem.202303250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 02/23/2024] [Accepted: 02/27/2024] [Indexed: 02/28/2024]
Abstract
Visible light-induced charge separation and directional charge transfer are cornerstones for artificial photosynthesis and the generation of solar fuels. Here, we report synthetic access to a series of noble metal-free donor-acceptor dyads based on bodipy light-absorbers and redox-active quinone/anthraquinone charge storage sites. Peripheral functionalization of the quinone/anthraquinone units with alkynes primes the dyads for integration into a range of light-harvesting systems, e. g., by Cu-catalyzed cycloadditions (CLICK chemistry) or Pd-catalyzed C-C cross-coupling reactions. Initial photophysical, electrochemical and theoretical analyses reveal the principal processes during the light-induced charge separation in the reported dyads.
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Affiliation(s)
- Sebastian Knoll
- Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Clara Zens
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743, Jena, Germany
| | - Tamar Maisuradze
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743, Jena, Germany
| | - Heiner Schmidt
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743, Jena, Germany
- Leibniz Institute of Photonic Technology, Albert-Einstein-Straße 9, 07745, Jena, Germany
| | - Stephan Kupfer
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743, Jena, Germany
| | - Linda Zedler
- Leibniz Institute of Photonic Technology, Albert-Einstein-Straße 9, 07745, Jena, Germany
| | - Benjamin Dietzek-Ivanšić
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743, Jena, Germany
- Leibniz Institute of Photonic Technology, Albert-Einstein-Straße 9, 07745, Jena, Germany
| | - Carsten Streb
- Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
- Department of Chemistry, Johannes Gutenberg University Mainz, Duesbergweg 10-14, 55128, Mainz, Germany
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2
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Ryland ES, Liu X, Kumar G, Raj SL, Xie ZL, Mengele AK, Fauth SS, Siewerth K, Dietzek-Ivanšić B, Rau S, Mulfort KL, Li X, Cordones AA. Site-specific electronic structure of covalently linked bimetallic dyads from nitrogen K-edge x-ray absorption spectroscopy. J Chem Phys 2024; 160:084307. [PMID: 38415835 DOI: 10.1063/5.0192809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 01/15/2024] [Indexed: 02/29/2024] Open
Abstract
A nitrogen K-edge x-ray absorption near-edge structure (XANES) survey is presented for tetrapyrido[3,2-a:2',3'-c:3″,2″-h:2‴,3‴-j]phenazine (tpphz)-bridged bimetallic assemblies that couple chromophore and catalyst transition metal complexes for light driven catalysis, as well as their individual molecular constituents. We demonstrate the high N site sensitivity of the N pre-edge XANES features, which are energetically well-separated for the phenazine bridge N atoms and for the individual metal-bound N atoms of the inner coordination sphere ligands. By comparison with the time-dependent density functional theory calculated spectra, we determine the origins of these distinguishable spectral features. We find that metal coordination generates large shifts toward higher energy for the metal-bound N atoms, with increasing shift for 3d < 4d < 5d metal bonding. This is attributed to increasing ligand-to-metal σ donation that increases the effective charge of the bound N atoms and stabilizes the N 1s core electrons. In contrast, the phenazine bridge N pre-edge peak is found at a lower energy due to stabilization of the low energy electron accepting orbital localized on the phenazine motif. While no sensitivity to ground state electronic coupling between the individual molecular subunits was observed, the spectra are sensitive to structural distortions of the tpphz bridge. These results demonstrate N K-edge XANES as a local probe of electronic structure in large bridging ligand motifs, able to distinctly investigate the ligand-centered orbitals involved in metal-to-ligand and ligand-to-ligand electron transfer following light absorption.
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Affiliation(s)
- Elizabeth S Ryland
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Xiaolin Liu
- University of Washington, Seattle, Washington 98195, USA
| | - Gaurav Kumar
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Sumana L Raj
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Zhu-Lin Xie
- Division of Chemical Sciences and Engineering, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Alexander K Mengele
- Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Sven S Fauth
- Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Kevin Siewerth
- Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Benjamin Dietzek-Ivanšić
- Leibniz Institute of Photonic Technology, Research Department Functional Interfaces, Albert-Einstein Straße 9, 07745 Jena, Germany and Friedrich Schiller University Jena, Institute of Physical Chemistry, Helmholtzweg 4, 07743 Jena, Germany
| | - Sven Rau
- Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Karen L Mulfort
- Division of Chemical Sciences and Engineering, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Xiaosong Li
- University of Washington, Seattle, Washington 98195, USA
| | - Amy A Cordones
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
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3
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Cancelliere AM, Arrigo A, Galletta M, Nastasi F, Campagna S, La Ganga G. Photo-driven water oxidation performed by supramolecular photocatalysts made of Ru(II) photosensitizers and catalysts. J Chem Phys 2024; 160:084709. [PMID: 38421072 DOI: 10.1063/5.0189316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 01/30/2024] [Indexed: 03/02/2024] Open
Abstract
Two new supramolecular photocatalysts made of covalently linked Ru(II) polypyridine chromophore subunits ([Ru(bpy)3]2+-type species; bpy = 2,2'-bipyridine) and [RuL(pic)2] (L = 2,2'-bipyridine-6,6'-dicarboxylic acid; pic = 4-picoline) water oxidation catalyst subunits have been prepared. The new species, 1 and 2, contain chromophore and catalyst subunits in the molecular ratios 1:1 and 1:2, respectively. The model chromophore species [Ru(bpy)2(L1)]2+ (RuP1; L1=4-[2-(4-pyridyl)-2-hydroxyethyl]-4-methyl-2,2'-bipyridine) and [Ru(bpy)2(L2)]2+ (RuP2; L2 = 4,4'-bis[2-(4-pyridyl)-2-hydroxyethyl]-2,2'-bipyridine) have also been prepared. The absorption spectra, oxidation behavior, and luminescent properties of 1 and 2 have been studied, and the results indicate that each subunit largely maintains its own properties in the supramolecular species. However, the luminescence of the chromophore subunits is significantly quenched in 1 and 2 in comparison with the luminescence of the respective model species. Both 1 and 2 exhibit catalytic water oxidation in the presence of cerium ammonium nitrate, exhibiting an I2M mechanism, with a better efficiency than the known catalyst [RuL(pic)2] under the same experimental conditions. Upon light irradiation, in the presence of persulfate as a sacrificial acceptor agent, 1 and 2 are more efficient photocatalysts than a system made of separated [Ru(bpy)3]2+ and [RuL(pic)2] species, highlighting the advantage of using multicomponent, supramolecular species with respect to isolated species. The O-O bond formation step is I2M, even in the photo-driven process. The photocatalytic process of 2 is more efficient than that of 1, with the turnover frequency reaching a value of 1.2 s-1. A possible reason could be an increased local concentration of catalytic subunits in the needed bimolecular assembly required for the I2M mechanism in 2 with respect to 1, a consequence of the presence of two catalytic subunits in each multicomponent species 2.
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Affiliation(s)
- Ambra M Cancelliere
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche e Ambientali, and Interuniversitary Research Center on Artificial Photosynthesis (SOLAR-CHEM, Messina Node), University of Messina, via F. Stagno d'Alcontres 31, 98166 Messina, Italy
| | - Antonino Arrigo
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche e Ambientali, and Interuniversitary Research Center on Artificial Photosynthesis (SOLAR-CHEM, Messina Node), University of Messina, via F. Stagno d'Alcontres 31, 98166 Messina, Italy
| | - Maurilio Galletta
- URT LABSENS DSFTM CNR, via F. Stagno d'Alcontres 31, 98166 Messina, Italy
| | - Francesco Nastasi
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche e Ambientali, and Interuniversitary Research Center on Artificial Photosynthesis (SOLAR-CHEM, Messina Node), University of Messina, via F. Stagno d'Alcontres 31, 98166 Messina, Italy
| | - Sebastiano Campagna
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche e Ambientali, and Interuniversitary Research Center on Artificial Photosynthesis (SOLAR-CHEM, Messina Node), University of Messina, via F. Stagno d'Alcontres 31, 98166 Messina, Italy
| | - Giuseppina La Ganga
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche e Ambientali, and Interuniversitary Research Center on Artificial Photosynthesis (SOLAR-CHEM, Messina Node), University of Messina, via F. Stagno d'Alcontres 31, 98166 Messina, Italy
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4
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Putra MH, Bagemihl B, Rau S, Groß A. Prediction of Strong Solvatochromism in a Molecular Photocatalyst. Chemistry 2024; 30:e202302643. [PMID: 37754665 DOI: 10.1002/chem.202302643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Revised: 09/25/2023] [Accepted: 09/25/2023] [Indexed: 09/28/2023]
Abstract
Based on quantum chemical calculations, we predict strong solvatochromism in a light-driven molecular photocatalyst for hydrogen generation, that is we show that the electronic and optical properties of the photocatalyst strongly depend on the solvent it is dissolved in. Our calculations in particular indicate a solvent-dependent relocation of the highest occupied molecular orbital (HOMO). Ground-state density functional theory and linear response time-dependent density functional theory calculations were applied in order to investigate the influence of implicit solvents on the structural, electronic and optical properties of a molecular photocatalyst. Only at high dielectric constants of the solvent, is the HOMO located at the metal center of the photosensitizer, whereas at low dielectric constants the HOMO is centered at the metal atom of the catalytically active complex. We elucidate the electronic origins of this strong solvatochromic effect and sketch the consequences of these insights for the use of photocatalysts in different environments.
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Affiliation(s)
| | - Benedikt Bagemihl
- Institute of Inorganic Chemistry I, Materials and Catalysis, Ulm University, 89069, Ulm, Germany
| | - Sven Rau
- Institute of Inorganic Chemistry I, Materials and Catalysis, Ulm University, 89069, Ulm, Germany
| | - Axel Groß
- Institute of Theoretical Chemistry, Ulm University, 89069, Ulm, Germany
- Helmholtz Institute Ulm (HIU), Electrochemical Energy Storage, 89069, Ulm, Germany
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5
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Zedler L, Kupfer S, Schmidt H, Dietzek-Ivanšić B. Oxidation-state sensitive light-induced dynamics of Ruthenium-4H-Imidazole complexes. Chemistry 2023:e202303079. [PMID: 38131166 DOI: 10.1002/chem.202303079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 12/20/2023] [Accepted: 12/22/2023] [Indexed: 12/23/2023]
Abstract
Oxidized molecular states are key intermediates in photo-induced redox reactions, e. g., intermolecular charge transfer between photosensitizer and catalyst in photoredox catalysis. The stability and longevity of the oxidized photosensitizer is an important factor in optimizing the respective light-driven reaction pathways. In this work the oxidized states of ruthenium(II)-4H-imidazole dyes are studied. The ruthenium complexes constitute benchmark photosensitizers in solar energy interconversion processes with exceptional chemical stability, strong visible light absorption, and favourable redox properties. To rationalize the light-induced reaction in the oxidized ruthenium(III) systems, we combine UV-vis absorption, resonance Raman, and transient absorption spectroelectrochemistry (SEC) with time-dependent density functional theory (TDDFT) calculations. Three complexes are compared, which vary with respect to their coordination environment, i. e., combining an 4H-imidazole with either 2,2'-bipyridine (bpy) or 2,2';6'2"-terpyridine (tpy) coligands, and chloride or isothiocyanate ligands. While all oxidized complexes have similar steady state absorption properties, their excited state kinetics differ significantly; the study thus opens the doorway to study the light-driven reactivity of oxidized molecular intermediates in intermolecular charge transfer cascades.
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Affiliation(s)
- Linda Zedler
- Functional Interfaces, Leibniz Institute of Photonic Technology, Albert-Einstein-Straße 9, 07745, Jena, Germany
| | - Stephan Kupfer
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743, Jena, Germany
| | - Heiner Schmidt
- Functional Interfaces, Leibniz Institute of Photonic Technology, Albert-Einstein-Straße 9, 07745, Jena, Germany
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743, Jena, Germany
| | - Benjamin Dietzek-Ivanšić
- Functional Interfaces, Leibniz Institute of Photonic Technology, Albert-Einstein-Straße 9, 07745, Jena, Germany
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743, Jena, Germany
- Jena Center for Soft Matter, Friedrich Schiller University Jena, Philosophenweg 7, 07743, Jena, Germany
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6
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Müller C, Kaufmann M, Brandon MP, Cullen AA, Dietzek-Ivanšić B, Pryce MT. New Twist on the Light-Switch Effect: Controlling the Fate of Excited States with pH in a 4-Hydroxy-thiazol-extended Ruthenium(II) Dppz Complex. J Phys Chem A 2023; 127:10613-10620. [PMID: 38059354 DOI: 10.1021/acs.jpca.3c06179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/08/2023]
Abstract
We present a pH-dependent study of the excited state dynamics of a novel Ru complex bearing a 4-hydroxy thiazol-substituted dppz (dipyridophenazine) ligand (RuTzOH) and its deprotonated form (RuTzO-). We combine steady-state and time-resolved absorption and emission spectroscopy with electrochemical investigations to characterize the excited state relaxation, which upon photoexcitation at 400 nm is determined by a multitude of initially populated MLCT states for both complexes. Subsequently, for RuTzOH, two long-lived excited states are populated, leading to dual emission from the complexes, a feature that vanishes upon deprotonation. Upon deprotonation, the electron density on the dppz moiety increases significantly, leading to rapid energy populating ligand-centered states and thus deactivating the initially excited MLCT states.
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Affiliation(s)
- Carolin Müller
- Computer Chemistry Center, Nägelsbachstraße 25, Friedrich-Alexander-University Erlangen-Nuremberg, 91052 Erlangen, Germany
| | - Martin Kaufmann
- School of Chemical Sciences, Dublin City University, D09 V209 Dublin, Ireland
| | - Michael P Brandon
- School of Chemical Sciences, Dublin City University, D09 V209 Dublin, Ireland
| | - Aoibhin A Cullen
- School of Chemical Sciences, Dublin City University, D09 V209 Dublin, Ireland
| | - Benjamin Dietzek-Ivanšić
- Friedrich Schiller University Jena, Institute of Physical Chemistry and Abbe Center of Photonics, Helmholtzweg 4, 07743 Jena, Germany
- Leibniz Institute of Photonic Technology, Research Department Functional Interfaces, Albert-Einstein-Straße 9, 07745 Jena, Germany
| | - Mary T Pryce
- School of Chemical Sciences, Dublin City University, D09 V209 Dublin, Ireland
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7
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Fickenscher Z, Hey-Hawkins E. Added Complexity!-Mechanistic Aspects of Heterobimetallic Complexes for Application in Homogeneous Catalysis. Molecules 2023; 28:4233. [PMID: 37241974 PMCID: PMC10224482 DOI: 10.3390/molecules28104233] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Revised: 05/16/2023] [Accepted: 05/17/2023] [Indexed: 05/28/2023] Open
Abstract
Inspired by multimetallic assemblies and their role in enzyme catalysis, chemists have developed a plethora of heterobimetallic complexes for application in homogeneous catalysis. Starting with small heterobimetallic complexes with σ-donating and π-accepting ligands, such as N-heterocyclic carbene and carbonyl ligands, more and more complex systems have been developed over the past two decades. These systems can show a significant increase in catalytic activity compared with their monometallic counterparts. This increase can be attributed to new reaction pathways enabled by the presence of a second metal center in the active catalyst. This review focuses on mechanistic aspects of heterobimetallic complexes in homogeneous catalysis. Depending on the type of interaction of the second metal with the substrates, heterobimetallic complexes can be subdivided into four classes. Each of these classes is illustrated with multiple examples, showcasing the versatility of both, the types of interactions possible, and the reactions accessible.
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Affiliation(s)
| | - Evamarie Hey-Hawkins
- Institute of Inorganic Chemistry, Universität Leipzig, Johannisallee 29, D-04103 Leipzig, Germany;
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8
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Brückmann J, Müller C, Friedländer I, Mengele AK, Peneva K, Dietzek‐Ivanšić B, Rau S. Photocatalytic Reduction of Nicotinamide Co-factor by Perylene Sensitized Rh III Complexes. Chemistry 2022; 28:e202201931. [PMID: 35920047 PMCID: PMC9825842 DOI: 10.1002/chem.202201931] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Indexed: 01/11/2023]
Abstract
The ambitious goal of artificial photosynthesis is to develop active systems that mimic nature and use light to split water into hydrogen and oxygen. Intramolecular design concepts are particularly promising. Herein, we firstly present an intramolecular photocatalyst integrating a perylene-based light-harvesting moiety and a catalytic rhodium center (RhIII phenPer). The excited-state dynamics were investigated by means of steady-state and time-resolved absorption and emission spectroscopy. The studies reveal that photoexcitation of RhIII phenPer yields the formation of a charge-separated intermediate, namely RhII phenPer⋅+ , that results in a catalytically active species in the presence of protons.
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Affiliation(s)
- Jannik Brückmann
- Institute of Inorganic Chemistry IUlm UniversityAlbert-Einstein-Allee 1189081UlmGermany
| | - Carolin Müller
- Institute of Physical ChemistryFriedrich Schiller University JenaHelmholtzweg 407743JenaGermany
- Research Department Functional InterfacesLeibniz Institute of Photonic Technology JenaAlbert-Einstein-Straße 907745JenaGermany
| | - Ilse Friedländer
- Institute of Physical ChemistryFriedrich Schiller University JenaHelmholtzweg 407743JenaGermany
| | - Alexander K. Mengele
- Institute of Inorganic Chemistry IUlm UniversityAlbert-Einstein-Allee 1189081UlmGermany
| | - Kalina Peneva
- Institute of Organic Chemistry and Macromolecular ChemistryFriedrich Schiller University JenaLessingstraße 807743JenaGermany
- Center for Energy and Environmental Chemistry Jena (CEEC Jena)Friedrich Schiller University JenaPhilosophenweg 7a07743JenaGermany
| | - Benjamin Dietzek‐Ivanšić
- Institute of Physical ChemistryFriedrich Schiller University JenaHelmholtzweg 407743JenaGermany
- Research Department Functional InterfacesLeibniz Institute of Photonic Technology JenaAlbert-Einstein-Straße 907745JenaGermany
- Center for Energy and Environmental Chemistry Jena (CEEC Jena)Friedrich Schiller University JenaPhilosophenweg 7a07743JenaGermany
| | - Sven Rau
- Institute of Inorganic Chemistry IUlm UniversityAlbert-Einstein-Allee 1189081UlmGermany
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9
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Brückmann J, Müller C, Maisuradze T, Mengele AK, Nauroozi D, Fauth S, Gruber A, Gräfe S, Leopold K, Kupfer S, Dietzek‐Ivanšić B, Rau S. Pyrimidoquinazolinophenanthroline Opens Next Chapter in Design of Bridging Ligands for Artificial Photosynthesis. Chemistry 2022; 28:e202200766. [PMID: 35719124 PMCID: PMC9546224 DOI: 10.1002/chem.202200766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Indexed: 11/08/2022]
Abstract
The synthesis and detailed characterization of a new Ru polypyridine complex containing a heteroditopic bridging ligand with previously unexplored metal-metal distances is presented. Due to the twisted geometry of the novel ligand, the resultant division of the ligand in two distinct subunits leads to steady state as well as excited state properties of the corresponding mononuclear Ru(II) polypyridine complex resembling those of prototype [Ru(bpy)3 ]2+ (bpy=2,2'-bipyridine). The localization of the initially optically excited and the nature of the long-lived excited states on the Ru-facing ligand spheres is evaluated by resonance Raman and fs-TA spectroscopy, respectively, and supported by DFT and TDDFT calculations. Coordination of a second metal (Zn or Rh) to the available bis-pyrimidyl-like coordination sphere strongly influences the frontier orbitals, apparent by, for example, luminescence quenching. Thus, the new bridging ligand motif offers electronic properties, which can be adjusted by the nature of the second metal center. Using the heterodinuclear Ru-Rh complex, visible light-driven reduction of NAD+ to NADH was achieved, highlighting the potential of this system for photocatalytic applications.
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Affiliation(s)
- Jannik Brückmann
- Institute of Inorganic Chemistry IUlm UniversityAlbert-Einstein-Allee 1189081UlmGermany
| | - Carolin Müller
- Institute of Physical ChemistryFriedrich-Schiller University JenaHelmholtzweg 407743JenaGermany
- Leibniz Institute of Photonic Technology (IPHT) e.V.Department Functional InterfacesAlbert-Einstein-Straße 907745JenaGermany
| | - Tamar Maisuradze
- Institute of Physical ChemistryFriedrich-Schiller University JenaHelmholtzweg 407743JenaGermany
| | - Alexander K. Mengele
- Institute of Inorganic Chemistry IUlm UniversityAlbert-Einstein-Allee 1189081UlmGermany
| | - Djawed Nauroozi
- Institute of Inorganic Chemistry IUlm UniversityAlbert-Einstein-Allee 1189081UlmGermany
| | - Sven Fauth
- Institute of Inorganic Chemistry IUlm UniversityAlbert-Einstein-Allee 1189081UlmGermany
| | - Andreas Gruber
- Institute of Analytical and Bioanalytical ChemistryUlm UniversityAlbert-Einstein-Allee 1189081UlmGermany
| | - Stefanie Gräfe
- Institute of Physical ChemistryFriedrich-Schiller University JenaHelmholtzweg 407743JenaGermany
| | - Kerstin Leopold
- Institute of Analytical and Bioanalytical ChemistryUlm UniversityAlbert-Einstein-Allee 1189081UlmGermany
| | - Stephan Kupfer
- Institute of Physical ChemistryFriedrich-Schiller University JenaHelmholtzweg 407743JenaGermany
| | - Benjamin Dietzek‐Ivanšić
- Institute of Physical ChemistryFriedrich-Schiller University JenaHelmholtzweg 407743JenaGermany
- Leibniz Institute of Photonic Technology (IPHT) e.V.Department Functional InterfacesAlbert-Einstein-Straße 907745JenaGermany
| | - Sven Rau
- Institute of Inorganic Chemistry IUlm UniversityAlbert-Einstein-Allee 1189081UlmGermany
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10
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Müller C, Pascher T, Eriksson A, Chabera P, Uhlig J. KiMoPack: A python Package for Kinetic Modeling of the Chemical Mechanism. J Phys Chem A 2022; 126:4087-4099. [PMID: 35700393 PMCID: PMC9251768 DOI: 10.1021/acs.jpca.2c00907] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Herein, we present
KiMoPack, an analysis tool for the kinetic modeling of transient spectroscopic data. KiMoPack
enables a state-of-the-art analysis routine including data preprocessing
and standard fitting (global analysis), as well as fitting of complex
(target) kinetic models, interactive viewing of (fit) results, and
multiexperiment analysis via user accessible functions and a graphical
user interface (GUI) enhanced interface. To facilitate its use, this
paper guides the user through typical operations covering a wide range
of analysis tasks, establishes a typical workflow and is bridging
the gap between ease of use for less experienced users and introducing
the advanced interfaces for experienced users. KiMoPack is open source
and provides a comprehensive front-end for preprocessing, fitting
and plotting of 2-dimensional data that simplifies the access to a
powerful python-based data-processing system
and forms the foundation for a well documented, reliable, and reproducible
data analysis.
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Affiliation(s)
- Carolin Müller
- Institute for Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany.,Leibniz Institute of Photonic Technology (IPHT) Jena, Albert-Einstein-Strasse 9, 07745 Jena, Germany
| | - Torbjörn Pascher
- Department of Chemical Physics, Lund University, SE-22100 Lund, Sweden
| | - Axl Eriksson
- Department of Chemical Physics, Lund University, SE-22100 Lund, Sweden
| | - Pavel Chabera
- Department of Chemical Physics, Lund University, SE-22100 Lund, Sweden
| | - Jens Uhlig
- Department of Chemical Physics, Lund University, SE-22100 Lund, Sweden
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11
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Zedler L, Müller C, Wintergerst P, Mengele AK, Rau S, Dietzek‐Ivanšić B. Influence of the Linker Chemistry on the Photoinduced Charge‐Transfer Dynamics of Hetero‐dinuclear Photocatalysts. Chemistry 2022; 28:e202200490. [PMID: 35481716 PMCID: PMC9325363 DOI: 10.1002/chem.202200490] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Indexed: 11/13/2022]
Abstract
To optimize light‐driven catalytic processes, light‐mediated multi‐electron transfer dynamics in molecular dyads need to be studied and correlated with structural changes focusing on the catalytically active metastable intermediates. Here, spectro‐electrochemistry has been employed to investigate the structure‐dependent photoelectron transfer kinetics in catalytically active intermediates of two Ru−Rh catalysts for light‐driven NAD+ reduction. The excited‐state reactivity of short‐lived intermediates was studied along different photoreaction pathways by resonance Raman and time‐resolved transient absorption spectro‐electrochemistry with sub‐picosecond time resolution under operando conditions. The results demonstrate, for the first time, how the bridging ligand serves as a (multi‐)electron storage structure, mediates the strength of the electronic coupling of catalytic and photocenter and impacts the targeted electron transfer as well as parasitic electron‐transfer kinetics.
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Affiliation(s)
- Linda Zedler
- Department Functional Interfaces Leibniz Institute of Photonic Technology Jena (Leibniz-IPHT) Albert-Einstein-Straße 9 07745 Jena Germany
| | - Carolin Müller
- Institute of Physical Chemistry Friedrich Schiller University Jena Helmholtzweg 4 07743 Jena Germany
| | - Pascal Wintergerst
- Department of Inorganic Chemistry I Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Alexander K. Mengele
- Department of Inorganic Chemistry I Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Sven Rau
- Department of Inorganic Chemistry I Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Benjamin Dietzek‐Ivanšić
- Department Functional Interfaces Leibniz Institute of Photonic Technology Jena (Leibniz-IPHT) Albert-Einstein-Straße 9 07745 Jena Germany
- Institute of Physical Chemistry Friedrich Schiller University Jena Helmholtzweg 4 07743 Jena Germany
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12
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Sinha N, Pfund B, Wegeberg C, Prescimone A, Wenger OS. Cobalt(III) Carbene Complex with an Electronic Excited-State Structure Similar to Cyclometalated Iridium(III) Compounds. J Am Chem Soc 2022; 144:9859-9873. [PMID: 35623627 PMCID: PMC9490849 DOI: 10.1021/jacs.2c02592] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
![]()
Many organometallic
iridium(III) complexes have photoactive excited
states with mixed metal-to-ligand and intraligand charge transfer
(MLCT/ILCT) character, which form the basis for numerous applications
in photophysics and photochemistry. Cobalt(III) complexes with analogous
MLCT excited-state properties seem to be unknown yet, despite the
fact that iridium(III) and cobalt(III) can adopt identical low-spin
d6 valence electron configurations due to their close chemical
relationship. Using a rigid tridentate chelate ligand (LCNC), in which a central amido π-donor is flanked by two σ-donating
N-heterocyclic carbene subunits, we obtained a robust homoleptic complex
[Co(LCNC)2](PF6), featuring a photoactive
excited state with substantial MLCT character. Compared to the vast
majority of isoelectronic iron(II) complexes, the MLCT state of [Co(LCNC)2](PF6) is long-lived because it
does not deactivate as efficiently into lower-lying metal-centered
excited states; furthermore, it engages directly in photoinduced electron
transfer reactions. The comparison with [Fe(LCNC)2](PF6), as well as structural, electrochemical, and UV–vis
transient absorption studies, provides insight into new ligand design
principles for first-row transition-metal complexes with photophysical
and photochemical properties reminiscent of those known from the platinum
group metals.
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Affiliation(s)
- Narayan Sinha
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Björn Pfund
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Christina Wegeberg
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Alessandro Prescimone
- Department of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, 4058 Basel, Switzerland
| | - Oliver S Wenger
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
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13
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Zedler L, Wintergerst P, Mengele AK, Müller C, Li C, Dietzek-Ivanšić B, Rau S. Outpacing conventional nicotinamide hydrogenation catalysis by a strongly communicating heterodinuclear photocatalyst. Nat Commun 2022; 13:2538. [PMID: 35534473 PMCID: PMC9085789 DOI: 10.1038/s41467-022-30147-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 04/14/2022] [Indexed: 11/30/2022] Open
Abstract
Unequivocal assignment of rate-limiting steps in supramolecular photocatalysts is of utmost importance to rationally optimize photocatalytic activity. By spectroscopic and catalytic analysis of a series of three structurally similar [(tbbpy)2Ru-BL-Rh(Cp*)Cl]3+ photocatalysts just differing in the central part (alkynyl, triazole or phenazine) of the bridging ligand (BL) we are able to derive design strategies for improved photocatalytic activity of this class of compounds (tbbpy = 4,4´-tert-butyl-2,2´-bipyridine, Cp* = pentamethylcyclopentadienyl). Most importantly, not the rate of the transfer of the first electron towards the RhIII center but rather the rate at which a two-fold reduced RhI species is generated can directly be correlated with the observed photocatalytic formation of NADH from NAD+. Interestingly, the complex which exhibits the fastest intramolecular electron transfer kinetics for the first electron is not the one that allows the fastest photocatalysis. With the photocatalytically most efficient alkynyl linked system, it is even possible to overcome the rate of thermal NADH formation by avoiding the rate-determining β-hydride elimination step. Moreover, for this photocatalyst loss of the alkynyl functionality under photocatalytic conditions is identified as an important deactivation pathway.
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Affiliation(s)
- Linda Zedler
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743, Jena, Germany
- Leibniz Institute of Photonic Technology Jena, Department Functional Interfaces, Albert-Einstein-Straße 9, 07745, Jena, Germany
| | - Pascal Wintergerst
- Institute of Inorganic Chemistry I, Materials and Catalysis, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Alexander K Mengele
- Institute of Inorganic Chemistry I, Materials and Catalysis, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Carolin Müller
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743, Jena, Germany
- Leibniz Institute of Photonic Technology Jena, Department Functional Interfaces, Albert-Einstein-Straße 9, 07745, Jena, Germany
| | - Chunyu Li
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743, Jena, Germany
- Leibniz Institute of Photonic Technology Jena, Department Functional Interfaces, Albert-Einstein-Straße 9, 07745, Jena, Germany
| | - Benjamin Dietzek-Ivanšić
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743, Jena, Germany.
- Leibniz Institute of Photonic Technology Jena, Department Functional Interfaces, Albert-Einstein-Straße 9, 07745, Jena, Germany.
- Center for Energy and Environmental Chemistry Jena (CEEC Jena), Philosophenweg 7a, 07743, Jena, Germany.
| | - Sven Rau
- Institute of Inorganic Chemistry I, Materials and Catalysis, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany.
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14
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Wu T, Kapitán J, Bouř P. Resolving Resonant Electronic States in Chiral Metal Complexes by Raman Optical Activity Spectroscopy. J Phys Chem Lett 2022; 13:3873-3877. [PMID: 35467874 DOI: 10.1021/acs.jpclett.2c00653] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Chiral metal complexes exhibit rich photophysical properties and are important for applications ranging from biosensing to photocatalysis. We present a combined experimental and computational approach leading to information about energies and transition moments of excited electronic states, documented on two chiral metal complexes. The experimental protocol for measurement of the resonance Raman optical activity comprises multiple techniques, i.e., absorption, circular dichroism, and polarized and differential Raman scattering. An accurate formula for subtraction of the interfering circular dichroism/polarized Raman scattering effect is given. An analysis of the spectra based on density functional theory calculations unveils the geometric and electronic structures of the molecules. Such insight into molecular electronic states of chromophores may be useful for understanding and tuning photochemical properties of metal-containing complexes, biomolecules, and supramolecules.
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Affiliation(s)
- Tao Wu
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences, Flemingovo náměstí 2, 16610 Prague, Czech Republic
| | - Josef Kapitán
- Department of Optics, Palacký University Olomouc, 17 Listopadu 12, 77146 Olomouc, Czech Republic
| | - Petr Bouř
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences, Flemingovo náměstí 2, 16610 Prague, Czech Republic
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15
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Herr P, Schwab A, Kupfer S, Wenger OS. Deep‐Red Luminescent Molybdenum(0) Complexes with Bi‐ and Tridentate Isocyanide Chelate Ligands. CHEMPHOTOCHEM 2022. [DOI: 10.1002/cptc.202200052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Patrick Herr
- University of Basel: Universitat Basel Department of Chemistry SWITZERLAND
| | - Alexander Schwab
- Friedrich-Schiller-Universität Jena: Friedrich-Schiller-Universitat Jena Institute of Physical Chemistry GERMANY
| | - Stephan Kupfer
- Friedrich-Schiller-Universität Jena: Friedrich-Schiller-Universitat Jena Institute of Physical Chemistry GERMANY
| | - Oliver S. Wenger
- Universität Basel Departement für Chemie St. Johanns-Ring 19 4056 Basel SWITZERLAND
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16
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Mengele AK, Weixler D, Amthor S, Eikmanns BJ, Seibold GM, Rau S. Transforming Escherichia coli Proteomembranes into Artificial Chloroplasts Using Molecular Photocatalysis. Angew Chem Int Ed Engl 2022; 61:e202114842. [PMID: 34932847 PMCID: PMC9306768 DOI: 10.1002/anie.202114842] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Indexed: 12/01/2022]
Abstract
During the light-dependent reaction of photosynthesis, green plants couple photoinduced cascades of redox reactions with transmembrane proton translocations to generate reducing equivalents and chemical energy in the form of NADPH (nicotinamide adenine dinucleotide phosphate) and ATP (adenosine triphosphate), respectively. We mimic these basic processes by combining molecular ruthenium polypyridine-based photocatalysts and inverted vesicles derived from Escherichia coli. Upon irradiation with visible light, the interplay of photocatalytic nicotinamide reduction and enzymatic membrane-located respiration leads to the simultaneous formation of two biologically active cofactors, NADH (nicotinamide adenine dinucleotide) and ATP, respectively. This inorganic-biologic hybrid system thus emulates the cofactor delivering function of an active chloroplast.
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Affiliation(s)
- Alexander K. Mengele
- Institute of Inorganic Chemistry IMaterials and CatalysisUlm UniversityAlbert-Einstein-Allee 1189081UlmGermany
| | - Dominik Weixler
- Institute of Microbiology and BiotechnologyUlm UniversityAlbert-Einstein-Allee 1189081UlmGermany
| | - Sebastian Amthor
- Institute of Inorganic Chemistry IMaterials and CatalysisUlm UniversityAlbert-Einstein-Allee 1189081UlmGermany
| | - Bernhard J. Eikmanns
- Institute of Microbiology and BiotechnologyUlm UniversityAlbert-Einstein-Allee 1189081UlmGermany
| | - Gerd M. Seibold
- Institute of Microbiology and BiotechnologyUlm UniversityAlbert-Einstein-Allee 1189081UlmGermany
- Section of Synthetic BiologyDepartment of Biotechnology and BioengineeringTechnical University of DenmarkSøltoftsplads2800Kongens LyngbyDenmark
| | - Sven Rau
- Institute of Inorganic Chemistry IMaterials and CatalysisUlm UniversityAlbert-Einstein-Allee 1189081UlmGermany
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17
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Active repair of a dinuclear photocatalyst for visible-light-driven hydrogen production. Nat Chem 2022; 14:500-506. [DOI: 10.1038/s41557-021-00860-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 11/19/2021] [Indexed: 12/30/2022]
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18
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Mengele AK, Weixler D, Amthor S, Eikmanns BJ, Seibold GM, Rau S. Transforming
Escherichia coli
Proteomembranes into Artificial Chloroplasts Using Molecular Photocatalysis. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202114842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Alexander K. Mengele
- Institute of Inorganic Chemistry I Materials and Catalysis Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Dominik Weixler
- Institute of Microbiology and Biotechnology Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Sebastian Amthor
- Institute of Inorganic Chemistry I Materials and Catalysis Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Bernhard J. Eikmanns
- Institute of Microbiology and Biotechnology Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Gerd M. Seibold
- Institute of Microbiology and Biotechnology Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
- Section of Synthetic Biology Department of Biotechnology and Bioengineering Technical University of Denmark Søltoftsplads 2800 Kongens Lyngby Denmark
| | - Sven Rau
- Institute of Inorganic Chemistry I Materials and Catalysis Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
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19
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Cerpentier FJR, Karlsson J, Lalrempuia R, Brandon MP, Sazanovich IV, Greetham GM, Gibson EA, Pryce MT. Ruthenium Assemblies for CO 2 Reduction and H 2 Generation: Time Resolved Infrared Spectroscopy, Spectroelectrochemistry and a Photocatalysis Study in Solution and on NiO. Front Chem 2022; 9:795877. [PMID: 35004612 PMCID: PMC8738169 DOI: 10.3389/fchem.2021.795877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 11/29/2021] [Indexed: 11/13/2022] Open
Abstract
Two novel supramolecular complexes RuRe ([Ru(dceb)2(bpt)Re(CO)3Cl](PF6)) and RuPt ([Ru(dceb)2(bpt)PtI(H2O)](PF6)2) [dceb = diethyl(2,2′-bipyridine)-4,4′-dicarboxylate, bpt = 3,5-di(pyridine-2-yl)-1,2,4-triazolate] were synthesized as new catalysts for photocatalytic CO2 reduction and H2 evolution, respectively. The influence of the catalytic metal for successful catalysis in solution and on a NiO semiconductor was examined. IR-active handles in the form of carbonyl groups on the peripheral ligand on the photosensitiser were used to study the excited states populated, as well as the one-electron reduced intermediate species using infrared and UV-Vis spectroelectrochemistry, and time resolved infrared spectroscopy. Inclusion of ethyl-ester moieties led to a reduction in the LUMO energies on the peripheral bipyridine ligand, resulting in localization of the 3MLCT excited state on these peripheral ligands following excitation. RuPt generated hydrogen in solution and when immobilized on NiO in a photoelectrochemical (PEC) cell. RuRe was inactive as a CO2 reduction catalyst in solution, and produced only trace amounts of CO when the photocatalyst was immobilized on NiO in a PEC cell saturated with CO2.
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Affiliation(s)
| | - Joshua Karlsson
- Energy Materials Laboratory, Department of Chemistry, School of Natural and Environmental Science, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Ralte Lalrempuia
- School of Chemical Sciences, Dublin City University, Dublin, Ireland.,Department of Chemistry, School of Physical Sciences, Mizoram University, Aizawl, India
| | - Michael P Brandon
- School of Chemical Sciences, Dublin City University, Dublin, Ireland
| | - Igor V Sazanovich
- Central Laser Facility, Science and Technology Facilities Council, Research Complex at Harwell, Rutherford Appleton Laboratory, Oxford, United Kingdom
| | - Gregory M Greetham
- Central Laser Facility, Science and Technology Facilities Council, Research Complex at Harwell, Rutherford Appleton Laboratory, Oxford, United Kingdom
| | - Elizabeth A Gibson
- Energy Materials Laboratory, Department of Chemistry, School of Natural and Environmental Science, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Mary T Pryce
- School of Chemical Sciences, Dublin City University, Dublin, Ireland
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20
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Mara MW, Phelan BT, Xie ZL, Kim TW, Hsu DJ, Liu X, Valentine AJS, Kim P, Li X, Adachi SI, Katayama T, Mulfort KL, Chen LX. Unveiling ultrafast dynamics in bridged bimetallic complexes using optical and X-ray transient absorption spectroscopies. Chem Sci 2022; 13:1715-1724. [PMID: 35282628 PMCID: PMC8827017 DOI: 10.1039/d1sc05034f] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 01/14/2022] [Indexed: 01/04/2023] Open
Abstract
In photosynthetic systems employing multiple transition metal centers, the properties of charge-transfer states are tuned by the coupling between metal centers. Here, we use ultrafast optical and X-ray spectroscopies to elucidate the effects of metal–metal interactions in a bimetallic tetrapyridophenazine-bridged Os(ii)/Cu(i) complex. Despite having an appropriate driving force for Os-to-Cu hole transfer in the Os(ii) moiety excited state, no such charge transfer was observed. However, excited-state coupling between the metal centers is present, evidenced by variations in the Os MLCT lifetime depending on the identity of the opposite metal center. This coupling results in concerted coherent vibrations appearing in the relaxation kinetics of the MLCT states for both Cu and Os centers. These vibrations are dominated by metal–ligand contraction at the Cu/Os centers, which are in-phase and linked through the conjugated bridging ligand. This study shows how vibronic coupling between transition metal centers affects the ultrafast dynamics in bridged, multi-metallic systems from the earliest times after photoexcitation to excited-state decay, presenting avenues for tuning charge-transfer states through judicious choice of metal/ligand groups. In photosynthetic systems employing multiple transition metal centers, the properties of charge-transfer states are tuned by the coupling between metal centers.![]()
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Affiliation(s)
- Michael W. Mara
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60437, USA
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA
| | - Brian T. Phelan
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60437, USA
| | - Zhu-Lin Xie
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60437, USA
| | - Tae Wu Kim
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60437, USA
| | - Darren J. Hsu
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA
| | - Xiaolin Liu
- Department of Chemistry, University of Washington, Seattle, Washington 98195, USA
| | | | - Pyosang Kim
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60437, USA
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA
| | - Xiaosong Li
- Department of Chemistry, University of Washington, Seattle, Washington 98195, USA
| | - Shin-ichi Adachi
- Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
- Department of Materials Structure Science, School of High Energy Accelerator Science, The Graduate University for Advanced Studies, 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - Tetsuo Katayama
- Japan Synchrotron Radiation Research Institute, Kouto 1-1-1, Sayo, Hyogo 679-5198, Japan
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
| | - Karen L. Mulfort
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60437, USA
| | - Lin X. Chen
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60437, USA
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA
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21
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Müller C, Friedländer I, Bagemihl B, Rau S, Dietzek-Ivanšić B. The electron that breaks the catalyst's back - excited state dynamics in intermediates of molecular photocatalysts. Phys Chem Chem Phys 2021; 23:27397-27403. [PMID: 34859807 DOI: 10.1039/d1cp04498b] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In situ spectroelectrochemical studies focussing on the Franck-Condon region and sub-ns electron transfer processes in Ru(II)-tpphz-Pt(II) based photocatalysts reveal that single-electron reduction effectively hinders intramolecular electron transfer between the photoexcited Ru chromophore and the Pt center.
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Affiliation(s)
- Carolin Müller
- Friedrich Schiller University Jena, Institute of Physical Chemistry, Helmholtzweg 4, 07743, Jena, Germany. .,Leibniz Institute of Photonic Technology, Research Department Functional Interfaces, Albert-Einstein-Str. 9, 07745, Jena, Germany
| | - Ilse Friedländer
- Leibniz Institute of Photonic Technology, Research Department Functional Interfaces, Albert-Einstein-Str. 9, 07745, Jena, Germany
| | - Benedikt Bagemihl
- Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Sven Rau
- Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Benjamin Dietzek-Ivanšić
- Friedrich Schiller University Jena, Institute of Physical Chemistry, Helmholtzweg 4, 07743, Jena, Germany. .,Leibniz Institute of Photonic Technology, Research Department Functional Interfaces, Albert-Einstein-Str. 9, 07745, Jena, Germany.,Friedrich Schiller University Jena, Center for Energy and Environmental Chemistry Jena (CEEC Jena), Lessingstraße 8, 07743 Jena, Germany
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22
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Isakov D, Schmid MA, Nauroozi D, Rau S, Tschierlei S. Prolonged Luminescence Lifetime of a Dual Emissive Ruthenium Dipyridophenazine-Type Complex in Aprotic and Protic Solvents. Inorg Chem 2021; 60:14002-14010. [PMID: 34495655 DOI: 10.1021/acs.inorgchem.1c01214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A recently reported ruthenium(II) complex bearing an extended dipyridophenazine ligand exhibits unusual long-lived dual emission at room temperature. In this study, the effect of the introduction of a methyl protecting group to the imidazole moiety of this ligand (L1, 11-methyl-11H-imidazo[4,5-i]dipyrido[3,2-a:2',3'-c]phenazine) on the photophysics of the respective ruthenium(II) complex [(tbbpy)2Ru(L1)]2+ (C1) is demonstrated by means of electrochemistry, UV/vis absorption and emission spectroscopy, as well as emission lifetime measurements, and transient absorption spectroscopy on the nanosecond time scale. At room temperature, C1 shows dual emission both in aprotic and in protic solvents with time constants of 1.1/34.2 and 1.2/8.4 μs, respectively. These lifetimes are assigned to the emission from 3MLCT and 3LC states. The introduction of the methyl group increases the lifetime of the 3LC state in C1 almost by a factor of 2 in acetonitrile solution compared to the previously reported compound. Accordingly, the newly introduced methyl group is described as a protecting group for the imidazole moiety of the heterocyclic ligand, which enables prolonged lifetimes of the dual emissive complex in protic solvents. The stabilization of the electronic structure is further underlined by the enhanced stability toward electrochemical reduction as evidenced by cyclic voltammetry.
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Affiliation(s)
- Dajana Isakov
- Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Marie-Ann Schmid
- Department of Energy Conversion, Institute of Physical and Theoretical Chemistry, Technische Universität Braunschweig, Gaußstraße 17, 38106 Braunschweig, Germany
| | - Djawed Nauroozi
- Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Sven Rau
- Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Stefanie Tschierlei
- Department of Energy Conversion, Institute of Physical and Theoretical Chemistry, Technische Universität Braunschweig, Gaußstraße 17, 38106 Braunschweig, Germany
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23
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Chari JV, Spence KA, Susick RB, Garg NK. A platform for on-the-complex annulation reactions with transient aryne intermediates. Nat Commun 2021; 12:3706. [PMID: 34140488 PMCID: PMC8211856 DOI: 10.1038/s41467-021-23970-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 05/25/2021] [Indexed: 11/09/2022] Open
Abstract
Organometallic complexes are ubiquitous in chemistry and biology. Whereas their preparation has historically relied on ligand synthesis followed by coordination to metal centers, the ability to efficiently diversify their structures remains a synthetic challenge. A promising yet underdeveloped strategy involves the direct manipulation of ligands that are already bound to a metal center, also known as chemistry-on-the-complex. Herein, we introduce a versatile platform for on-the-complex annulation reactions using transient aryne intermediates. In one variant, organometallic complexes undergo transition metal-catalyzed annulations with in situ generated arynes to form up to six new carbon-carbon bonds. In the other variant, an organometallic complex bearing a free aryne is generated and intercepted in cycloaddition reactions to access unique scaffolds. Our studies, centered around privileged polypyridyl metal complexes, provide an effective strategy to annulate organometallic complexes and access complex metal-ligand scaffolds, while furthering the synthetic utility of strained intermediates in chemical synthesis.
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Affiliation(s)
- Jason V Chari
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
| | - Katie A Spence
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
| | - Robert B Susick
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
| | - Neil K Garg
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA.
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24
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Nair SS, Bysewski OA, Kupfer S, Wächtler M, Winter A, Schubert US, Dietzek B. Excitation Energy-Dependent Branching Dynamics Determines Photostability of Iron(II)-Mesoionic Carbene Complexes. Inorg Chem 2021; 60:9157-9173. [PMID: 34081456 DOI: 10.1021/acs.inorgchem.1c01166] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Photoactive metal complexes containing earth-abundant transition metals recently gained interest as photosensitizers in light-driven chemistry. In contrast to the traditionally employed ruthenium or iridium complexes, iron complexes developed to be promising candidates despite the fact that using iron complexes as photosensitizers poses an inherent challenge associated with the low-lying metal-centered states, which are responsible for ultrafast deactivation of the charge-transfer states. Nonetheless, recent developments of strongly σ-donating carbene ligands yielded highly promising systems, in which destabilized metal-centered states resulted in prolonged lifetimes of charge-transfer excited states. In this context, we introduce a series of novel homoleptic Fe-triazolylidene mesoionic carbene complexes. The excited-state properties of the complexes were investigated by time-resolved femtosecond transient absorption spectroscopy and quantum chemical calculations. Pump wavelength-dependent transient absorption reveals the presence of distinct excited-state relaxation pathways. We relate the excitation-wavelength-dependent branching of the excited-state dynamics into various reaction channels to solvent-dependent photodissociation following the population of dissociative metal centered states upon excitation at 400 nm.
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Affiliation(s)
- Shruthi S Nair
- Department Functional Interfaces, Leibniz Institute of Photonic Technology (Leibniz-IPHT), Albert-Einstein-Strasse 9, 07745 Jena, Germany.,Institute of Physical Chemistry, Friedrich-Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany
| | - Oliver A Bysewski
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich-Schiller University Jena, Humboldtstrasse 10, 07743 Jena, Germany.,Center for Energy and Environmental Chemistry Jena (CEEC-Jena), Friedrich-Schiller University Jena, Philosophenweg, 07743 Jena, Germany
| | - Stephan Kupfer
- Institute of Physical Chemistry, Friedrich-Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany
| | - Maria Wächtler
- Department Functional Interfaces, Leibniz Institute of Photonic Technology (Leibniz-IPHT), Albert-Einstein-Strasse 9, 07745 Jena, Germany.,Institute of Physical Chemistry, Friedrich-Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany.,Abbe Center of Photonics, Friedrich Schiller University Jena, Philosophenweg, 07745 Jena, Germany
| | - Andreas Winter
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich-Schiller University Jena, Humboldtstrasse 10, 07743 Jena, Germany.,Center for Energy and Environmental Chemistry Jena (CEEC-Jena), Friedrich-Schiller University Jena, Philosophenweg, 07743 Jena, Germany
| | - Ulrich S Schubert
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich-Schiller University Jena, Humboldtstrasse 10, 07743 Jena, Germany.,Center for Energy and Environmental Chemistry Jena (CEEC-Jena), Friedrich-Schiller University Jena, Philosophenweg, 07743 Jena, Germany
| | - Benjamin Dietzek
- Department Functional Interfaces, Leibniz Institute of Photonic Technology (Leibniz-IPHT), Albert-Einstein-Strasse 9, 07745 Jena, Germany.,Institute of Physical Chemistry, Friedrich-Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany
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25
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Bold S, Massin J, Giannoudis E, Koepf M, Artero V, Dietzek B, Chavarot-Kerlidou M. Spectroscopic Investigations Provide a Rationale for the Hydrogen-Evolving Activity of Dye-Sensitized Photocathodes Based on a Cobalt Tetraazamacrocyclic Catalyst. ACS Catal 2021. [DOI: 10.1021/acscatal.0c05033] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Sebastian Bold
- Laboratoire de Chimie et Biologie des Métaux, Univ.́ Grenoble Alpes, CNRS, CEA, IRIG, 17 rue des Martyrs, F-38000 Grenoble, France
- Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany
- Department Functional Interfaces, Leibniz Institute of Photonic Technology Jena (Leibniz-IPHT), Albert-Einstein-Straße 9, 07745 Jena, Germany
| | - Julien Massin
- Laboratoire de Chimie et Biologie des Métaux, Univ.́ Grenoble Alpes, CNRS, CEA, IRIG, 17 rue des Martyrs, F-38000 Grenoble, France
| | - Emmanouil Giannoudis
- Laboratoire de Chimie et Biologie des Métaux, Univ.́ Grenoble Alpes, CNRS, CEA, IRIG, 17 rue des Martyrs, F-38000 Grenoble, France
| | - Matthieu Koepf
- Laboratoire de Chimie et Biologie des Métaux, Univ.́ Grenoble Alpes, CNRS, CEA, IRIG, 17 rue des Martyrs, F-38000 Grenoble, France
| | - Vincent Artero
- Laboratoire de Chimie et Biologie des Métaux, Univ.́ Grenoble Alpes, CNRS, CEA, IRIG, 17 rue des Martyrs, F-38000 Grenoble, France
| | - Benjamin Dietzek
- Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany
- Department Functional Interfaces, Leibniz Institute of Photonic Technology Jena (Leibniz-IPHT), Albert-Einstein-Straße 9, 07745 Jena, Germany
- Center for Energy and Environmental Chemistry Jena (CEEC Jena), Friedrich Schiller University Jena, Philosophenweg 8, 07743 Jena, Germany
| | - Murielle Chavarot-Kerlidou
- Laboratoire de Chimie et Biologie des Métaux, Univ.́ Grenoble Alpes, CNRS, CEA, IRIG, 17 rue des Martyrs, F-38000 Grenoble, France
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26
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Photocathodes beyond NiO: charge transfer dynamics in a π-conjugated polymer functionalized with Ru photosensitizers. Sci Rep 2021; 11:2787. [PMID: 33531588 PMCID: PMC7854750 DOI: 10.1038/s41598-021-82395-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 01/19/2021] [Indexed: 11/09/2022] Open
Abstract
A conductive polymer (poly(p-phenylenevinylene), PPV) was covalently modified with RuII complexes to develop an all-polymer photocathode as a conceptual alternative to dye-sensitized NiO, which is the current state-of-the-art photocathode in solar fuels research. Photocathodes require efficient light-induced charge-transfer processes and we investigated these processes within our photocathodes using spectroscopic and spectro-electrochemical techniques. Ultrafast hole-injection dynamics in the polymer were investigated by transient absorption spectroscopy and charge transfer at the electrode-electrolyte interface was examined with chopped-light chronoamperometry. Light-induced hole injection from the photosensitizers into the PPV backbone was observed within 10 ps and the resulting charge-separated state (CSS) recombined within ~ 5 ns. This is comparable to CSS lifetimes of conventional NiO-photocathodes. Chopped-light chronoamperometry indicates enhanced charge-transfer at the electrode-electrolyte interface upon sensitization of the PPV with the RuII complexes and p-type behavior of the photocathode. The results presented here show that the polymer backbone behaves like classical molecularly sensitized NiO photocathodes and operates as a hole accepting semiconductor. This in turn demonstrates the feasibility of all-polymer photocathodes for application in solar energy conversion.
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27
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Kranz C, Wächtler M. Characterizing photocatalysts for water splitting: from atoms to bulk and from slow to ultrafast processes. Chem Soc Rev 2021; 50:1407-1437. [DOI: 10.1039/d0cs00526f] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
This review provides a comprehensive overview on characterisation techniques for light-driven redox-catalysts highlighting spectroscopic, microscopic, electrochemical and spectroelectrochemical approaches.
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Affiliation(s)
- Christine Kranz
- Ulm University
- Institute of Analytical and Bioanalytical Chemistry
- 89081 Ulm
- Germany
| | - Maria Wächtler
- Leibniz Institute of Photonic Technology
- Department Functional Interfaces
- 07745 Jena
- Germany
- Friedrich Schiller University Jena
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28
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Luo Y, Maloul S, Wächtler M, Winter A, Schubert US, Streb C, Dietzek B. Is electron ping-pong limiting the catalytic hydrogen evolution activity in covalent photosensitizer-polyoxometalate dyads? Chem Commun (Camb) 2020; 56:10485-10488. [PMID: 32766633 DOI: 10.1039/d0cc04509h] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Understanding the limitations of catalytic processes enables the design of optimized catalysts. Here, femtosecond transient absorption spectroelectrochemistry is used to explore the photophysics of polyoxometalate-based covalent photosensitizer-hydrogen evolution catalyst dyads. The study shows that the presence of light-driven forward and backward electron transfer, i.e. "electron ping-pong", is a limiting factor for charge accumulation on the polyoxometalate. Based on this insight, chemical means of optimizing catalyst performance are proposed.
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Affiliation(s)
- Yusen Luo
- Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich-Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany and Department Functional Interfaces, Leibniz Institute of Photonic Technology (IPHT), Albert-Einstein-Strasse 9, 07745 Jena, Germany.
| | - Salam Maloul
- Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany.
| | - Maria Wächtler
- Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich-Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany and Department Functional Interfaces, Leibniz Institute of Photonic Technology (IPHT), Albert-Einstein-Strasse 9, 07745 Jena, Germany.
| | - Andreas Winter
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich-Schiller University Jena, Humboldtstrasse 10, 07743 Jena, Germany and Center for Energy and Environmental Chemistry Jena (CEEC-Jena), Friedrich-Schiller University Jena, Philosophenweg 7a, 07743 Jena, Germany
| | - Ulrich S Schubert
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich-Schiller University Jena, Humboldtstrasse 10, 07743 Jena, Germany and Center for Energy and Environmental Chemistry Jena (CEEC-Jena), Friedrich-Schiller University Jena, Philosophenweg 7a, 07743 Jena, Germany
| | - Carsten Streb
- Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany.
| | - Benjamin Dietzek
- Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich-Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany and Department Functional Interfaces, Leibniz Institute of Photonic Technology (IPHT), Albert-Einstein-Strasse 9, 07745 Jena, Germany. and Center for Energy and Environmental Chemistry Jena (CEEC-Jena), Friedrich-Schiller University Jena, Philosophenweg 7a, 07743 Jena, Germany
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29
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Schreier MR, Pfund B, Guo X, Wenger OS. Photo-triggered hydrogen atom transfer from an iridium hydride complex to unactivated olefins. Chem Sci 2020; 11:8582-8594. [PMID: 34123118 PMCID: PMC8163408 DOI: 10.1039/d0sc01820a] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 07/27/2020] [Indexed: 12/18/2022] Open
Abstract
Many photoactive metal complexes can act as electron donors or acceptors upon photoexcitation, but hydrogen atom transfer (HAT) reactivity is rare. We discovered that a typical representative of a widely used class of iridium hydride complexes acts as an H-atom donor to unactivated olefins upon irradiation at 470 nm in the presence of tertiary alkyl amines as sacrificial electron and proton sources. The catalytic hydrogenation of simple olefins served as a test ground to establish this new photo-reactivity of iridium hydrides. Substrates that are very difficult to activate by photoinduced electron transfer were readily hydrogenated, and structure-reactivity relationships established with 12 different olefins are in line with typical HAT reactivity, reflecting the relative stabilities of radical intermediates formed by HAT. Radical clock, H/D isotope labeling, and transient absorption experiments provide further mechanistic insight and corroborate the interpretation of the overall reactivity in terms of photo-triggered hydrogen atom transfer (photo-HAT). The catalytically active species is identified as an Ir(ii) hydride with an IrII-H bond dissociation free energy around 44 kcal mol-1, which is formed after reductive 3MLCT excited-state quenching of the corresponding Ir(iii) hydride, i.e. the actual HAT step occurs on the ground-state potential energy surface. The photo-HAT reactivity presented here represents a conceptually novel approach to photocatalysis with metal complexes, which is fundamentally different from the many prior studies relying on photoinduced electron transfer.
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Affiliation(s)
- Mirjam R Schreier
- Department of Chemistry, University of Basel St. Johanns-Ring 19 4056 Basel Switzerland
| | - Björn Pfund
- Department of Chemistry, University of Basel St. Johanns-Ring 19 4056 Basel Switzerland
| | - Xingwei Guo
- Department of Chemistry, University of Basel St. Johanns-Ring 19 4056 Basel Switzerland
| | - Oliver S Wenger
- Department of Chemistry, University of Basel St. Johanns-Ring 19 4056 Basel Switzerland
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30
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Mengele AK, Rau S. The Metallic Traveler: Formate- and Photoinduced Regioselective Phenanthroline Deuterations via Reductively Activated RhCp* Centers. Organometallics 2020. [DOI: 10.1021/acs.organomet.0c00341] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Alexander K. Mengele
- Institute of Inorganic Chemistry I, Materials and Catalysis, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Sven Rau
- Institute of Inorganic Chemistry I, Materials and Catalysis, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
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31
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Zedler L, Mengele AK, Ziems KM, Zhang Y, Wächtler M, Gräfe S, Pascher T, Rau S, Kupfer S, Dietzek B. Unraveling the Light-Activated Reaction Mechanism in a Catalytically Competent Key Intermediate of a Multifunctional Molecular Catalyst for Artificial Photosynthesis. Angew Chem Int Ed Engl 2019; 58:13140-13148. [PMID: 31347251 PMCID: PMC6772164 DOI: 10.1002/anie.201907247] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Indexed: 11/07/2022]
Abstract
Understanding photodriven multielectron reaction pathways requires the identification and spectroscopic characterization of intermediates and their excited-state dynamics, which is very challenging due to their short lifetimes. To the best of our knowledge, this manuscript reports for the first time on in situ spectroelectrochemistry as an alternative approach to study the excited-state properties of reactive intermediates of photocatalytic cycles. UV/Vis, resonance-Raman, and transient-absorption spectroscopy have been employed to characterize the catalytically competent intermediate [(tbbpy)2 RuII (tpphz)RhI Cp*] of [(tbbpy)2 Ru(tpphz)Rh(Cp*)Cl]Cl(PF6 )2 (Ru(tpphz)RhCp*), a photocatalyst for the hydrogenation of nicotinamide (NAD-analogue) and proton reduction, generated by electrochemical and chemical reduction. Electronic transitions shifting electron density from the activated catalytic center to the bridging tpphz ligand significantly reduce the catalytic activity upon visible-light irradiation.
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Affiliation(s)
- Linda Zedler
- Department Functional InterfacesLeibniz Institute of Photonic Technology Jena (IPHT)Albert-Einstein-Straße 907745JenaGermany
| | | | - Karl Michael Ziems
- Institute of Physical Chemistry and Abbe Center of PhotonicsFriedrich Schiller University JenaHelmholtzweg 407743JenaGermany
| | - Ying Zhang
- Department Functional InterfacesLeibniz Institute of Photonic Technology Jena (IPHT)Albert-Einstein-Straße 907745JenaGermany
- Institute of Physical Chemistry and Abbe Center of PhotonicsFriedrich Schiller University JenaHelmholtzweg 407743JenaGermany
| | - Maria Wächtler
- Department Functional InterfacesLeibniz Institute of Photonic Technology Jena (IPHT)Albert-Einstein-Straße 907745JenaGermany
- Institute of Physical Chemistry and Abbe Center of PhotonicsFriedrich Schiller University JenaHelmholtzweg 407743JenaGermany
| | - Stefanie Gräfe
- Institute of Physical Chemistry and Abbe Center of PhotonicsFriedrich Schiller University JenaHelmholtzweg 407743JenaGermany
| | | | - Sven Rau
- Department of Inorganic Chemistry IUniversity of UlmAlbert-Einstein-Allee 1189081UlmGermany
| | - Stephan Kupfer
- Institute of Physical Chemistry and Abbe Center of PhotonicsFriedrich Schiller University JenaHelmholtzweg 407743JenaGermany
| | - Benjamin Dietzek
- Department Functional InterfacesLeibniz Institute of Photonic Technology Jena (IPHT)Albert-Einstein-Straße 907745JenaGermany
- Institute of Physical Chemistry and Abbe Center of PhotonicsFriedrich Schiller University JenaHelmholtzweg 407743JenaGermany
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