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Utschig LM, Mulfort KL. Photosynthetic biohybrid systems for solar fuels catalysis. Chem Commun (Camb) 2024. [PMID: 39229971 DOI: 10.1039/d4cc00774c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/05/2024]
Abstract
Photosynthetic reaction center (RC) proteins are finely tuned molecular systems optimized for solar energy conversion. RCs effectively capture and convert sunlight with near unity quantum efficiency utilizing light-induced directional electron transfer through a series of molecular cofactors embedded within the protein core to generate a long-lived charge separated state with a useable electrochemical potential. Of current interest are new strategies that couple RC chemistry to the direct synthesis of energy-rich compounds. This Feature Article highlights recent work from our lab on RC and RC-inspired hybrid systems that capture the Sun's energy and convert it to chemical energy in the form of H2, a carbon-neutral energy source derived from water. Biohybrids made from the Photosystem I (PSI) RC are among the best photocatalytic H2-producing protein hybrids to date. Targeted self-assembly strategies that couple abiotic catalysts to PSI translate to catalyst incorporation at intrinsic PSI sites within thylakoid membranes to achieve complete solar water-splitting systems. RC-inspired biohybrids interface synthetic photosensitizers and molecular catalysts with small proteins to create photocatalytic systems and enable the spectroscopic discernment of the structural features and electron transfer processes that underpin solar-driven proton reduction. In total, these studies showcase the incredible scientific opportunities photosynthetic biohybrid research provides for harnessing the optimal qualities of both artificial and natural photosynthetic systems and developing materials that capture, convert, and store solar energy as a fuel.
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Affiliation(s)
- Lisa M Utschig
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL 60439, USA.
| | - Karen L Mulfort
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL 60439, USA.
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2
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Akogun FS, Judd M, Mort AGC, Malthus SJ, Robb MG, Cox N, Brooker S. Complexes of a Noncyclic Carbazole-based N5-donor Schiff base: Structures, Redox, EPR and Poor Activity as Hydrogen Evolution Electrocatalysts. Inorg Chem 2024. [PMID: 39225072 DOI: 10.1021/acs.inorgchem.4c02657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
A new noncyclic pentadentate N5-donor Schiff-base ligand, HL2Etpyr (1,1'-(3,6-ditert-butyl-9H-carbazole-1,8-diyl)bis(N-(2-(pyridin-2-yl)ethyl)methanimine)), prepared from 1,8-diformyl-3,6-ditertbutyl-carbazole (HUtBu) and two equivalents of 2-(2-pyridyl)ethylamine, along with four tetrafluoroborate complexes, [MIIL2Etpyr](BF4), where M = Co, Ni, Cu, and Zn, and two [CoIIL2EtPyr]·1/2[CoIIX4] complexes where X = NCS or Cl, isolated as solvates, are reported. All six complexes were structurally characterized, revealing the cations to be isostructural, with M(II) in a trigonal bipyramidal N5-donor environment. Only the Zn(II) complex is fluorescent. Cyclic voltammograms of [MIIL2Etpyr](BF4) in MeCN reveal reversible redox processes at positive potentials: 0.61 (Zn), 0.62 (Cu), 0.57 (Ni), and 0.25 V (Co), and for the cobalt complex a second quasi-reversible process occurs at 0.92 V vs Fc+/Fc. EPR data for the first oxidation product clearly demonstrate that the Zn complex undergoes a ligand centered oxidation, and support this being the case for the Ni and Cu complexes, although this is not definitively shown. After both oxidations the EPR data shows that the Co complex is best described as a low spin Co(III)-ligand radical. In the presence of 80 mM acetic acid, controlled potential electrolysis carried out on [MIIL2Etpyr](BF4) at -1.68 V in MeCN shows some electrocatalytic hydrogen evolution reaction (HER) performance in the order Ni(II) > Cu(II) > Co(II) - but the control, Ni(II) tetrafluoroborate, is more active than all three of the complexes.
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Affiliation(s)
- Folaranmi S Akogun
- Department of Chemistry and MacDiarmid Institute for Advanced Materials and Nanotechnology, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Martyna Judd
- Research School of Chemistry, The Australian National University, Canberra, ACT 0200, Australia
| | - Alexandra G C Mort
- Research School of Chemistry, The Australian National University, Canberra, ACT 0200, Australia
| | - Stuart J Malthus
- Department of Chemistry and MacDiarmid Institute for Advanced Materials and Nanotechnology, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Matthew G Robb
- Department of Chemistry and MacDiarmid Institute for Advanced Materials and Nanotechnology, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Nicholas Cox
- Research School of Chemistry, The Australian National University, Canberra, ACT 0200, Australia
| | - Sally Brooker
- Department of Chemistry and MacDiarmid Institute for Advanced Materials and Nanotechnology, University of Otago, PO Box 56, Dunedin 9054, New Zealand
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Fortage J, Collomb MN, Costentin C. Turnover Number in Photoinduced Molecular Catalysis of Hydrogen Evolution: a Benchmarking for Catalysts? CHEMSUSCHEM 2024:e202400205. [PMID: 38529822 DOI: 10.1002/cssc.202400205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 03/22/2024] [Accepted: 03/26/2024] [Indexed: 03/27/2024]
Abstract
Development of devices for production of H2 using light and a sustainable source of electrons may require the design of molecular systems combining a molecular catalyst and a photosensitizer. Evaluation of the efficiency of hydrogen production is commonly performed in homogeneous solution with a sacrificial electron donor and the report of the maximal turnover number vs catalyst (T O N c a t lim ${TON_{cat}^{\lim } }$ ). This figure of merit is strongly dependent on deactivation pathways and does not by itself provide a benchmarking for catalysts. In particular, when the photosensitizer degradation is the primary source of limitation, a kinetic model, rationalizing literature data, shows that a decrease of the catalyst concentration leads to an increase ofT O N c a t lim ${TON_{cat}^{\lim } }$ . It indicates that exceptionally highT O N c a t lim ${TON_{cat}^{\lim } }$ obtained at very low catalyst concentration shall not be considered as an indication of an exceptional catalytic system. We advocate for a systematic kinetic analysis in order to get a quantitative measure of the competitive pathways leading toT O N c a t lim ${TON_{cat}^{\lim } }$ values and to provide keys for performance improvement.
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Affiliation(s)
- Jérôme Fortage
- Département de Chimie Moléculaire, Univ. Grenoble Alpes, CNRS, 38000, Grenoble, France
| | - Marie-Noëlle Collomb
- Département de Chimie Moléculaire, Univ. Grenoble Alpes, CNRS, 38000, Grenoble, France
| | - Cyrille Costentin
- Département de Chimie Moléculaire, Univ. Grenoble Alpes, CNRS, 38000, Grenoble, France
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Thammanatpong K, Surawatanawong P. Mechanisms of hydrogen evolution by six-coordinate cobalt complexes: a density functional study on the role of a redox-active pyridinyl-substituted diaminotriazine benzamidine ligand as a proton relay. Dalton Trans 2024; 53:6006-6019. [PMID: 38469898 DOI: 10.1039/d3dt03960a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
The hydrogen evolution reaction is an important process for energy storage. The six-coordinate cobalt complex [CoIII(L1-)(LH)]2+ (LH = N-(4-amino-6-(pyridin-2-yl)-1,3,5-triazin-2-yl)benzamidine) was found to catalyze photocatalytic hydrogen evolution. In this work, we performed density functional calculations to obtain the reduction potentials and the proton-transfer free energy of possible intermediates to determine the preferred pathways for proton reduction. The mechanism involves the metal-based reduction of Co(III) to Co(II) before the protonation at the amidinate N on the pyridinyl-substituted diaminotriazine benzamidinate ligand L1- to form [CoII(LH)(LH)]2+. Essentially, the subsequent electron transfer is not metal-based reduction, but rather ligand-based reduction to form [CoII(LH)(LH˙1-)]1+. Through a proton-coupled electron transfer process, the cobalt hydride [CoIIH(LH)(LH2˙)]1+ is formed as the key intermediate for hydrogen evolution. As the cobalt hydride complex is coordinatively saturated, a structural change is required when the hydride on Co is coupled with the proton on pyridine. Notably, the redox-active nature of the ligand results in the low acidity of the protonated pyridine moiety of LH2˙, which impedes its function as a proton relay. Our findings suggest that separating the proton relay fragment from the electron reservoir fragment of the redox-active ligand is preferred for fully utilizing both features in catalytic H2 evolution.
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Affiliation(s)
- Kittimeth Thammanatpong
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahidol University, Bangkok 10400, Thailand.
| | - Panida Surawatanawong
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahidol University, Bangkok 10400, Thailand.
- Center of Sustainable Energy and Green Materials, Mahidol University, Salaya, Nakhon Pathom 73170, Thailand
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5
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Adhikari S, Sheikh AH, Kansız S, Dege N, Baildya N, Mahmoudi G, Choudhury NA, Butcher RJ, Kaminsky W, Talledo S, Lopato EM, Bernhard S, Kłak J. Supramolecular Co(II) Complexes Based on Dithiolate and Dicarboxylate Ligands: Crystal structures, Theoretical studies, Magnetic Properties, and Catalytic Activity Studies in Photocatalytic Hydrogen Evolution. J Mol Struct 2023. [DOI: 10.1016/j.molstruc.2023.135481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
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6
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Su C, Chen Z, Feng Q, Wei F, Zhang M, Mo A, Huang HH, Hu H, Liu D. Highly Efficient Visible-Light-Driven CO 2-to-CO Conversion by Coordinatively Unsaturated Co-Salen Complexes in a Water-Containing System. Inorg Chem 2022; 61:19748-19755. [PMID: 36417273 DOI: 10.1021/acs.inorgchem.2c02515] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The development of cost-effective catalysts for CO2 reduction is highly desired but remains a significant challenge. The unsaturated coordination metal center in a catalyst is favorable for the process of catalytic CO2 reduction. In this paper, two asymmetric salen ligands were used to synthesize two coordinatively unsaturated Co-salen complexes. The two Co-salen complexes exhibit an unsaturated coordination pattern and display high activity and CO selectivity for visible-light-driven CO2 reduction in a water-containing system. The photocatalytic performance of 2 is higher than that of 1 because the reduction potential of the catalytic CoII center and the energy barrier of the catalytic transition states of 2 are lower than those of 1, with turnover numbers (TONCO), turnover frequencies (TOF), and CO selectivity values of 8640, 0.24 s-1, and 97% for 2, respectively. The photocatalytic reduction of CO2 to CO for 2 is well supported by control experiments and density functional theory (DFT) calculations.
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Affiliation(s)
- Chao Su
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Collaborative Innovation Center for Guangxi Ethnic Medicine, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, No. 15 Yucai Road, Guilin 541004, China
| | - Zilu Chen
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Collaborative Innovation Center for Guangxi Ethnic Medicine, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, No. 15 Yucai Road, Guilin 541004, China
| | - Qin Feng
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Collaborative Innovation Center for Guangxi Ethnic Medicine, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, No. 15 Yucai Road, Guilin 541004, China
| | - Fangsha Wei
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Collaborative Innovation Center for Guangxi Ethnic Medicine, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, No. 15 Yucai Road, Guilin 541004, China
| | - Mingling Zhang
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Collaborative Innovation Center for Guangxi Ethnic Medicine, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, No. 15 Yucai Road, Guilin 541004, China
| | - Anna Mo
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Collaborative Innovation Center for Guangxi Ethnic Medicine, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, No. 15 Yucai Road, Guilin 541004, China
| | - Hai-Hua Huang
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Collaborative Innovation Center for Guangxi Ethnic Medicine, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, No. 15 Yucai Road, Guilin 541004, China
| | - Huancheng Hu
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Collaborative Innovation Center for Guangxi Ethnic Medicine, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, No. 15 Yucai Road, Guilin 541004, China
| | - Dongcheng Liu
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Collaborative Innovation Center for Guangxi Ethnic Medicine, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, No. 15 Yucai Road, Guilin 541004, China
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Droghetti F, Lucarini F, Molinari A, Ruggi A, Natali M. Recent findings and future directions in photosynthetic hydrogen evolution using polypyridine cobalt complexes. Dalton Trans 2022; 51:10658-10673. [PMID: 35475511 PMCID: PMC9936794 DOI: 10.1039/d2dt00476c] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The production of hydrogen gas using water as the molecular substrate currently represents one of the most challenging and appealing reaction schemes in the field of artificial photosynthesis (AP), i.e., the conversion of solar energy into fuels. In order to be efficient, this process requires a suitable combination of a light-harvesting sensitizer, an electron donor, and a hydrogen-evolving catalyst (HEC). In the last few years, cobalt polypyridine complexes have been discovered to be competent molecular catalysts for the hydrogen evolution reaction (HER), showing enhanced efficiency and stability with respect to previously reported molecular species. This perspective collects information about all relevant cobalt polypyridine complexes employed for the HER in aqueous solution under light-driven conditions in the presence of Ru(bpy)32+ (where bpy = 2,2'-bipyridine) as the photosensitizer and ascorbate as the electron donor, trying to highlight promising chemical motifs and aiming towards efficient catalytic activity in order to stimulate further efforts to design molecular catalysts for hydrogen generation and allow their profitable implementation in devices. As a final step, a few suggestions for the benchmarking of HECs employed under light-driven conditions are introduced.
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Affiliation(s)
- Federico Droghetti
- Department of Chemical, Pharmaceutical, and Agricultural Sciences (DOCPAS), University of Ferrara, Via L. Borsari 46, 44121 Ferrara, Italy.
| | - Fiorella Lucarini
- Département de Chimie, Université de Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland.
| | - Alessandra Molinari
- Department of Chemical, Pharmaceutical, and Agricultural Sciences (DOCPAS), University of Ferrara, Via L. Borsari 46, 44121 Ferrara, Italy.
| | - Albert Ruggi
- Département de Chimie, Université de Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland.
| | - Mirco Natali
- Department of Chemical, Pharmaceutical, and Agricultural Sciences (DOCPAS), University of Ferrara, Via L. Borsari 46, 44121 Ferrara, Italy. .,Centro Interuniversitario per la Conversione Chimica dell'Energia Solare (SolarChem), sez. di Ferrara, Via L. Borsari 46, 44121 Ferrara, Italy
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8
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Costentin C, Camara F, Fortage J, Collomb MN. Photoinduced Catalysis of Redox Reactions. Turnover Numbers, Turnover Frequency, and Limiting Processes: Kinetic Analysis and Application to Light-Driven Hydrogen Production. ACS Catal 2022. [DOI: 10.1021/acscatal.2c01289] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Cyrille Costentin
- Univ Grenoble Alpes, DCM, CNRS, 38000 Grenoble, France
- Université Paris Cité, 75013 Paris, France
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9
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Dinda S, Sarkar K, Panda BK, Pramanik K, Ganguly S. Diarylazooxime complex of cobalt(III): synthesis, structure, ligand redox, DFT calculations and spectral characteristics. TRANSIT METAL CHEM 2022. [DOI: 10.1007/s11243-021-00485-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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10
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Rajak S, Vu NN, Kaur P, Duong A, Nguyen-Tri P. Recent progress on the design and development of diaminotriazine based molecular catalysts for light-driven hydrogen production. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2021.214375] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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11
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Singh V, Abudayyeh A, Robb MG, Brooker S. Mono-copper far more active than analogous di-copper complex for electrocatalytic hydrogen evolution. Dalton Trans 2022; 51:4166-4172. [DOI: 10.1039/d2dt00141a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The di-copper(II) analogue, [CuII2(bis-LEt)](BF4)2 (2), of the previously reported mono-copper(II) complex [CuIILEt]BF4 (1) which resulted in long lived electrocatalytic hydrogen evolution reaction (HER), has been prepared, characterised and tested for...
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12
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Gamache MT, Auvray T, Kurth DG, Hanan GS. Dinuclear 2,4-di(pyridin-2-yl)-pyrimidine based ruthenium photosensitizers for hydrogen photo-evolution under red light. Dalton Trans 2021; 50:16528-16538. [PMID: 34698748 DOI: 10.1039/d1dt00868d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this study, we report two dinuclear Ru(II) complexes C1 and C2 and compare them to their mononuclear analogues Ref1 and Ref2. The dinuclear species exhibit a much stronger absorption, longer excited-state lifetimes and higher luminescence quantum yields than the mononuclear complexes. In addition, C1 and C2 are easier to reduce. An estimation of the driving forces for the electron transfer processes relevant to photocatalytic hydrogen evolution suggests that C1 and Ref2 possess similar activity as photosensitizer (PS). Yet, the improved photophysical properties of C1 make it a more promising candidate for hydrogen evolution. In hydrogen evolution experiments, C1 indeed exhibits increased activity as PS, however, the catalytic system loses its activity after only a few hours. C2 is less active than the mononuclear complexes despite its superior photophysical properties. This observation is attributed to a lack of driving force for the electron transfer towards the catalyst. Further studies of the dinuclear complex C1 show that it is indeed the PS, which decomposes under the catalytic conditions, presumably due to the electron transfer towards the catalyst being the rate-limiting step.
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Affiliation(s)
- Mira T Gamache
- Chemische Technologie der Materialsynthese, Julius-Maximilians-Universität Würzburg, Röntgenring 11, 97070 Würzburg, Germany.,Département de Chimie, Université de Montréal, 1375 Avenue Thérèse-Lavoie-Roux, Montréal, Québec, H2V-03B, Canada
| | - Thomas Auvray
- Département de Chimie, Université de Montréal, 1375 Avenue Thérèse-Lavoie-Roux, Montréal, Québec, H2V-03B, Canada
| | - Dirk G Kurth
- Chemische Technologie der Materialsynthese, Julius-Maximilians-Universität Würzburg, Röntgenring 11, 97070 Würzburg, Germany
| | - Garry S Hanan
- Département de Chimie, Université de Montréal, 1375 Avenue Thérèse-Lavoie-Roux, Montréal, Québec, H2V-03B, Canada
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13
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Oswald E, Gaus AL, Kund J, Küllmer M, Romer J, Weizenegger S, Ullrich T, Mengele AK, Petermann L, Leiter R, Unwin PR, Kaiser U, Rau S, Kahnt A, Turchanin A, von Delius M, Kranz C. Cobaloxime Complex Salts: Synthesis, Patterning on Carbon Nanomembranes and Heterogeneous Hydrogen Evolution Studies. Chemistry 2021; 27:16896-16903. [PMID: 34713512 PMCID: PMC9299159 DOI: 10.1002/chem.202102778] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Indexed: 12/26/2022]
Abstract
Cobaloximes are promising, earth‐abundant catalysts for the light‐driven hydrogen evolution reaction (HER). Typically, these cobalt(III) complexes are prepared in situ or employed in their neutral form, for example, [Co(dmgH)2(py)Cl], even though related complex salts have been reported previously and could, in principle, offer improved catalytic activity as well as more efficient immobilization on solid support. Herein, we report an interdisciplinary investigation into complex salts [Co(dmgH)2(py)2]+[Co(dmgBPh2)2Cl2]−, TBA+[Co(dmgBPh2)2Cl2]-
and [Co(dmgH)2(py)2]+BArF−. We describe their strategic syntheses from the commercially available complex [Co(dmgH)2(py)Cl] and demonstrate that these double and single complex salts are potent catalysts for the light‐driven HER. We also show that scanning electrochemical cell microscopy can be used to deposit arrays of catalysts [Co(dmgH)2(py)2]+[Co(dmgBPh2)2Cl2]−, TBA+[Co(dmgBPh2)2Cl2]-
and [Co(dmgH)2(py)Cl] on supported and free‐standing amino‐terminated ∼1‐nm‐thick carbon nanomembranes (CNMs). Photocatalytic H2 evolution at such arrays was quantified with Pd microsensors by scanning electrochemical microscopy, thus providing a new approach for catalytic evaluation and opening up novel routes for the creation and analysis of “designer catalyst arrays”, nanoprinted in a desired pattern on a solid support.
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Affiliation(s)
- Eva Oswald
- Institute of Analytical and Bioanalytical Chemistry, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Anna-Laurine Gaus
- Institute of Organic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Julian Kund
- Institute of Analytical and Bioanalytical Chemistry, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Maria Küllmer
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Lessingstrasse 10, 07743, Jena, Germany
| | - Jan Romer
- Institute of Analytical and Bioanalytical Chemistry, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Simon Weizenegger
- Institute of Organic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Tobias Ullrich
- Department of Chemistry and Pharmacy, Friedrich Alexander University Erlangen-Nürnberg, Egerlandstrasse 3, 91058, Erlangen, Germany
| | - Alexander K Mengele
- Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Lydia Petermann
- Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Robert Leiter
- Central Facility Electron Microscopy, Materials Science Electron Microscopy, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Patrick R Unwin
- Department of Chemistry, University of Warwick, Gibbet Hill Road, CV4 7AL, Coventry, UK
| | - Ute Kaiser
- Central Facility Electron Microscopy, Materials Science Electron Microscopy, 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
| | - Axel Kahnt
- Leibniz-Institute of Surface Engineering (IOM), Permoserstrasse 15, 04318, Leipzig, Germany
| | - Andrey Turchanin
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Lessingstrasse 10, 07743, Jena, Germany
| | - Max von Delius
- Institute of Organic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Christine Kranz
- Institute of Analytical and Bioanalytical Chemistry, Albert-Einstein-Allee 11, 89081, Ulm, Germany
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14
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Lucarini F, Bongni D, Schiel P, Bevini G, Benazzi E, Solari E, Fadaei-Tirani F, Scopelliti R, Marazzi M, Natali M, Pastore M, Ruggi A. Rationalizing Photo-Triggered Hydrogen Evolution Using Polypyridine Cobalt Complexes: Substituent Effects on Hexadentate Chelating Ligands. CHEMSUSCHEM 2021; 14:1874-1885. [PMID: 33650260 DOI: 10.1002/cssc.202100161] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 02/16/2021] [Indexed: 06/12/2023]
Abstract
Four novel polypyridine cobalt(II) complexes were developed based on a hexadentate ligand scaffold bearing either electron-withdrawing (-CF3 ) or electron-donating (-OCH3 ) groups in different positions of the ligand. Experiments and theoretical calculations were combined to perform a systematic investigation of the effect of the ligand modification on the hydrogen evolution reaction. The results indicated that the position, rather than the type of substituent, was the dominating factor in promoting catalysis. The best performances were observed upon introduction of substituents on the pyridine moiety of the hexadentate ligand, which promoted the formation of the Co(II)H intermediate via intramolecular proton transfer reactions with low activation energy. Quantum yields of 11.3 and 10.1 %, maximum turnover frequencies of 86.1 and 76.6 min-1 , and maximum turnover numbers of 5520 and 4043 were obtained, respectively, with a -OCH3 and a -CF3 substituent.
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Affiliation(s)
- Fiorella Lucarini
- Université de Fribourg Département de Chimie, Chemin du Musée 9, 1700, Fribourg, Switzerland
| | - David Bongni
- Université de Fribourg Département de Chimie, Chemin du Musée 9, 1700, Fribourg, Switzerland
| | - Philippe Schiel
- Université de Fribourg Département de Chimie, Chemin du Musée 9, 1700, Fribourg, Switzerland
| | - Gabriele Bevini
- Università degli studi di Ferrara Dipartimento di Scienze Chimiche, Farmaceutiche ed Agrarie, Via L. Borsari 46, 44121, Ferrara, Italy
| | - Elisabetta Benazzi
- Università degli studi di Ferrara Dipartimento di Scienze Chimiche, Farmaceutiche ed Agrarie, Via L. Borsari 46, 44121, Ferrara, Italy
| | - Euro Solari
- Institut des Sciences et Ingénierie Chimique, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Farzaneh Fadaei-Tirani
- Institut des Sciences et Ingénierie Chimique, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Rosario Scopelliti
- Institut des Sciences et Ingénierie Chimique, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Marco Marazzi
- Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, Universidad de Alcalá, Ctra. Madrid-Barcelona Km. 33,600, E-28805 Alcalá de Henares, Madrid), Spain
- Chemical Research Institute "Andrés M. del Río" (IQAR), Universidad de Alcalá, 28871 Alcalá de Henares, Madrid), Spain
| | - Mirco Natali
- Università degli studi di Ferrara Dipartimento di Scienze Chimiche, Farmaceutiche ed Agrarie, Via L. Borsari 46, 44121, Ferrara, Italy
| | - Mariachiara Pastore
- Université de Lorraine & CNRS, Laboratoire de Physique et Chimie Théoriques (LPCT), 54000, Nancy, France
| | - Albert Ruggi
- Université de Fribourg Département de Chimie, Chemin du Musée 9, 1700, Fribourg, Switzerland
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15
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Celestine MJ, Lawrence MA, Schott O, Picard V, Hanan GS, Marquez EM, Harold CG, Kuester CT, Frenzel BA, Hamaker CG, Hightower SE, McMillen CD, Holder AA. Synthesis, structure, and hydrogen evolution studies of a heteroleptic Co(III) complex. Inorganica Chim Acta 2021. [DOI: 10.1016/j.ica.2020.120195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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16
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Recent progress in homogeneous light-driven hydrogen evolution using first-row transition metal catalysts. Inorganica Chim Acta 2021. [DOI: 10.1016/j.ica.2020.119950] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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17
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Rodríguez-Jiménez S, Bennington MS, Akbarinejad A, Tay EJ, Chan EWC, Wan Z, Abudayyeh AM, Baek P, Feltham HLC, Barker D, Gordon KC, Travas-Sejdic J, Brooker S. Electroactive Metal Complexes Covalently Attached to Conductive PEDOT Films: A Spectroelectrochemical Study. ACS APPLIED MATERIALS & INTERFACES 2021; 13:1301-1313. [PMID: 33351602 DOI: 10.1021/acsami.0c16317] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The successful covalent attachment, via copper(I)-catalyzed azide alkyne cycloaddition (CuAAC), of alkyne-functionalized nickel(II) and copper(II) macrocyclic complexes onto azide (N3)-functionalized poly(3,4-ethylenedioxythiophene) (PEDOT) films on ITO-coated glass electrodes is reported. To investigate the surface attachment of the selected metal complexes, which are analogues of the cobalt-based complex previously reported to be a molecular catalyst for hydrogen evolution, first, three different PEDOT films were formed by electropolymerization of pure PEDOT or pure N3-PEDOT, and last, 1:2N3-PEDOT:PEDOT were formed by co-polymerizing a 1:4 mixture of N3-EDOT:EDOT monomers. The successful surface immobilization of the complexes on the latter two azide-functionalized films, by CuAAC, was confirmed by X-ray photoelectron spectroscopy (XPS) and electrochemistry as well as by UV-vis-NIR and resonance Raman spectroelectrochemistry. The ratio between the N3 groups, and hence, the number of surface-attached metal complexes after CuAAC functionalization, in pristine N3-PEDOT versus 1:2N3-PEDOT:PEDOT is expected to be 3:1 and seen to be 2.86:1 with a calculated surface coverage of 3.28 ± 1.04 and 1.15 ± 0.09 nmol/cm2, respectively. The conversion, to the metal complex attached films, was lower for the N3-PEDOT films (Ni 74%, Cu 76%) than for the copolymer 1:2N3-PEDOT:PEDOT films (Ni 83%, Cu 91%) due to the former being more sterically congested. The Raman and UV-vis-NIR results were simulated using density functional theory (DFT) and time-dependent DFT (TD-DFT), respectively, and showed good agreement with the experimental data. Importantly, the spectroelectrochemical behavior of both anchored metal complexes is analogous to that of the free metal complexes in solution. This proves that PEDOT films are promising conducting scaffolds for the covalent immobilization of metal complexes, as the existing electrochromic features of the complexes are preserved on immobilization, which is important for applications in electrocatalytic proton and carbon dioxide reduction, optoelectronics, and sensing.
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Affiliation(s)
- Santiago Rodríguez-Jiménez
- Department of Chemistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand
| | - Michael S Bennington
- Department of Chemistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand
| | - Alireza Akbarinejad
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand
- Polymer Biointerface Centre and School of Chemical Sciences, The University of Auckland, Auckland 1010, New Zealand
| | - Elliot J Tay
- Department of Chemistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand
| | - Eddie Wai Chi Chan
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand
- Polymer Biointerface Centre and School of Chemical Sciences, The University of Auckland, Auckland 1010, New Zealand
| | - Ziyao Wan
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand
- Polymer Biointerface Centre and School of Chemical Sciences, The University of Auckland, Auckland 1010, New Zealand
| | - Abdullah M Abudayyeh
- Department of Chemistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand
| | - Paul Baek
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand
- Polymer Biointerface Centre and School of Chemical Sciences, The University of Auckland, Auckland 1010, New Zealand
| | - Humphrey L C Feltham
- Department of Chemistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand
| | - David Barker
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand
- Polymer Biointerface Centre and School of Chemical Sciences, The University of Auckland, Auckland 1010, New Zealand
| | - Keith C Gordon
- Department of Chemistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand
| | - Jadranka Travas-Sejdic
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand
- Polymer Biointerface Centre and School of Chemical Sciences, The University of Auckland, Auckland 1010, New Zealand
| | - Sally Brooker
- Department of Chemistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand
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18
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Replacing Pyridine with Pyrazine in Molecular Cobalt Catalysts: Effects on Electrochemical Properties and Aqueous H2 Generation. Catalysts 2021. [DOI: 10.3390/catal11010075] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Four new molecular Co(II)tetrapyridyl complexes were synthesized and evaluated for their activity as catalysts for proton reduction in aqueous environments. The pyridine groups around the macrocycle were substituted for either one or two pyrazine groups. Single crystal X-ray analysis shows that the pyrazine groups have minimal impact on the Co(II)–N bond lengths and molecular geometry in general. X-band EPR spectroscopy confirms the Co(II) oxidation state and the electronic environment of the Co(II) center are only very slightly perturbed by the substitution of pyrazine groups around the macrocycle. The substitution of pyrazine groups has a substantial impact on the observed metal- and ligand-centered reduction potentials as well as the overall H2 catalytic activity in a multimolecular system using the [Ru(2,2′-bipyridine)3]Cl2 photosensitizer and ascorbic acid as a sacrificial electron donor. The results reveal interesting trends between the H2 catalytic activity for each catalyst and the driving force for electron transfer between either the reduced photosensitizer to catalyst step or the catalyst to proton reduction step. The work presented here showcases how even the difference of a single atom in a molecular catalyst can have an important impact on activity and suggests a pathway to optimize the photocatalytic activity and stability of molecular systems.
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19
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Rupp MT, Auvray T, Shevchenko N, Swoboda L, Hanan GS, Kurth DG. Substituted 2,4-Di(pyridin-2-yl)pyrimidine-Based Ruthenium Photosensitizers for Hydrogen Photoevolution under Red Light. Inorg Chem 2021; 60:292-302. [PMID: 33322895 DOI: 10.1021/acs.inorgchem.0c02955] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The photocatalytic reduction of water to form hydrogen gas (H2) is a promising approach to collect, convert, and store solar energy. Typically, ruthenium tris(bipyridine) and its many derivatives are used as photosensitizers (PSs) in a variety of photocatalytic conditions. The bis(terpyridine) analogues, however, have only recently gained attention for this application because of their poor photophysical properties. Yet, by the introduction of electron-donating or -withdrawing groups on the terpyridine ligands, the photophysical and electrochemical properties can be considerably improved. In this study, we report a series of nonsymmetric 2,6-di(pyridin-2-yl)pyrimidine ligands with peripheral pyridine substituents in different positions and their corresponding ruthenium(II) complexes. The presence of the pyrimidine ring stabilizes the lowest unoccupied molecular orbital, leading to a red-shifted emission and prolonged excited-state lifetimes as well as higher luminescence quantum yields compared to analogous terpyridine complexes. Furthermore, all complexes are easier to reduce than the previously reported bis(terpyridine) complexes used as PSs. Interestingly, the pyridine substituent in the 4-pyrimidine position has a greater impact on both the photophysical and electrochemical properties. This correlation between the substitution pattern and properties of the complexes is further investigated by using time-dependent density functional theory. In hydrogen evolution experiments under blue- and red-light irradiation, all investigated complexes exhibit much higher activity compared to the previously reported ruthenium(II) bis(terpyridine) complexes, but none of the complexes are as stable as the literature compounds, presumably because of an additional decomposition pathway of the reduced PS competing with electron transfer from the reduced PS to the catalyst.
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Affiliation(s)
- Mira T Rupp
- Département de Chimie, Université de Montréal, 1375 Avenue Thérèse-Lavoie-Roux, Montréal, Québec H2 V-03B, Canada.,Chemische Technologie der Materialsynthese, Julius-Maximilians-Universität Würzburg, Röntgenring 11, Würzburg 97070, Germany
| | - Thomas Auvray
- Département de Chimie, Université de Montréal, 1375 Avenue Thérèse-Lavoie-Roux, Montréal, Québec H2 V-03B, Canada
| | - Natali Shevchenko
- Département de Chimie, Université de Montréal, 1375 Avenue Thérèse-Lavoie-Roux, Montréal, Québec H2 V-03B, Canada
| | - Lukas Swoboda
- Chemische Technologie der Materialsynthese, Julius-Maximilians-Universität Würzburg, Röntgenring 11, Würzburg 97070, Germany
| | - Garry S Hanan
- Département de Chimie, Université de Montréal, 1375 Avenue Thérèse-Lavoie-Roux, Montréal, Québec H2 V-03B, Canada
| | - Dirk G Kurth
- Chemische Technologie der Materialsynthese, Julius-Maximilians-Universität Würzburg, Röntgenring 11, Würzburg 97070, Germany
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20
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Abudayyeh AM, Schott O, Feltham HLC, Hanan GS, Brooker S. Copper catalysts for photo- and electro-catalytic hydrogen production. Inorg Chem Front 2021. [DOI: 10.1039/d0qi01247e] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Square planar 1, square pyramidal 2 and trigonal bipyramidal 3 copper complexes are poor catalysts for hydrogen evolution (HER) under photocatalytic conditions, whereas 1 is, or forms, a good and enduring electrocatalyst for HER, but 2 and 3 do not.
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Affiliation(s)
- Abdullah M. Abudayyeh
- Department of Chemistry and the MacDiarmid Institute for Advanced Materials and Nanotechnology
- University of Otago
- Dunedin 9054
- New Zealand
| | - Olivier Schott
- Départment de Chimie
- Université de Montréal
- Montréal
- Canada
| | - Humphrey L. C. Feltham
- Department of Chemistry and the MacDiarmid Institute for Advanced Materials and Nanotechnology
- University of Otago
- Dunedin 9054
- New Zealand
| | - Garry S. Hanan
- Départment de Chimie
- Université de Montréal
- Montréal
- Canada
| | - Sally Brooker
- Department of Chemistry and the MacDiarmid Institute for Advanced Materials and Nanotechnology
- University of Otago
- Dunedin 9054
- New Zealand
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21
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Hong YH, Lee YM, Nam W, Fukuzumi S. Photocatalytic Hydrogen Evolution from Plastoquinol Analogues as a Potential Functional Model of Photosystem I. Inorg Chem 2020; 59:14838-14846. [PMID: 33023288 DOI: 10.1021/acs.inorgchem.0c02254] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The recent development of a functional model of photosystem II (PSII) has paved a new way to connect the PSII model with a functional model of photosystem I (PSI). However, PSI functional models have yet to be reported. We report herein the first potential functional model of PSI, in which plastoquinol (PQH2) analogues were oxidized to plastoquinone (PQ) analogues, accompanied by hydrogen (H2) evolution. Photoirradiation of a deaerated acetonitrile (MeCN) solution containing hydroquinone derivatives (X-QH2) as a hydrogen source, 9-mesityl-10-methylacridinium ion (Acr+-Mes) as a photoredox catalyst, and a cobalt(III) complex, CoIII(dmgH)2pyCl (dmgH = dimethylglyoximate monoanion; py = pyridine) as a redox catalyst resulted in the evolution of H2 and formation of the corresponding p-benzoquinone derivatives (X-Q) quantitatively. The maximum quantum yield for photocatalytic H2 evolution from tetrachlorohydroquinone (Cl4QH2) with Acr+-Mes and CoIII(dmgH)2pyCl and H2O in deaerated MeCN was determined to be 10%. Photocatalytic H2 evolution is started by electron transfer (ET) from Cl4QH2 to the triplet ET state of Acr+-Mes to produce Cl4QH2•+ and Acr•-Mes with a rate constant of 7.2 × 107 M-1 s-1, followed by ET from Acr•-Mes to CoIII(dmgH)2pyCl to produce [CoII(dmgH)2pyCl]-, accompanied by the regeneration of Acr+-Mes. On the other hand, Cl4QH2•+ is deprotonated to produce Cl4QH•, which transfers either a hydrogen-atom transfer or a proton-coupled electron transfer to [CoII(dmgH)2pyCl]- to produce a cobalt(III) hydride complex, [CoIII(H)(dmgH)2pyCl]-, which reacts with H+ to evolve H2, accompanied by the regeneration of CoIII(dmgH)2pyCl. The formation of [CoII(dmgH)2pyCl]- was detected by electron paramagnetic resonance measurements.
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Affiliation(s)
- Young Hyun Hong
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Yong-Min Lee
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Wonwoo Nam
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea.,School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710119, China
| | - Shunichi Fukuzumi
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea.,Faculty of Science and Engineering, Meijo University, Nagoya, Aichi 468-0073, Japan
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22
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Rajak S, Chair K, Rana LK, Kaur P, Maris T, Duong A. Amidine/Amidinate Cobalt Complexes: One-Pot Synthesis, Mechanism, and Photocatalytic Application for Hydrogen Production. Inorg Chem 2020; 59:14910-14919. [DOI: 10.1021/acs.inorgchem.0c01495] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sanil Rajak
- Département de Chimie, Biochimie et Physique and Institut de Recherche sur l’Hydrogène, Université du Québec à Trois-Rivières, Trois-Rivières, Québec G9A 5H7, Canada
| | - Khaoula Chair
- Département de Chimie, Biochimie et Physique and Institut de Recherche sur l’Hydrogène, Université du Québec à Trois-Rivières, Trois-Rivières, Québec G9A 5H7, Canada
| | - Love Karan Rana
- Département de Chimie, Biochimie et Physique and Institut de Recherche sur l’Hydrogène, Université du Québec à Trois-Rivières, Trois-Rivières, Québec G9A 5H7, Canada
| | - Prabhjyot Kaur
- Département de Chimie, Biochimie et Physique and Institut de Recherche sur l’Hydrogène, Université du Québec à Trois-Rivières, Trois-Rivières, Québec G9A 5H7, Canada
| | - Thierry Maris
- Département de Chimie, Université de Montréal, Montréal, Québec H3C 3J7, Canada
| | - Adam Duong
- Département de Chimie, Biochimie et Physique and Institut de Recherche sur l’Hydrogène, Université du Québec à Trois-Rivières, Trois-Rivières, Québec G9A 5H7, Canada
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23
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Celestine MJ, Lawrence MA, Evaristo NK, Legere BW, Knarr JK, Schott O, Picard V, Bullock JL, Hanan GS, McMillen CD, Bayse CA, Holder AA. N-substituted 2-pyridinecarbothioamides and polypyridyl mixed-ligand cobalt(III)-containing complexes for photocatalytic hydrogen generation. Inorganica Chim Acta 2020. [DOI: 10.1016/j.ica.2020.119726] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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24
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Rajak S, Schott O, Kaur P, Maris T, Hanan GS, Duong A. Synthesis, crystal structure, characterization of pyrazine diaminotriazine based complexes and their systematic comparative study with pyridyl diaminotriazine based complexes for light-driven hydrogen production. Polyhedron 2020. [DOI: 10.1016/j.poly.2020.114412] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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25
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Understanding metal synergy in heterodinuclear catalysts for the copolymerization of CO2 and epoxides. Nat Chem 2020; 12:372-380. [DOI: 10.1038/s41557-020-0450-3] [Citation(s) in RCA: 130] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 02/27/2020] [Indexed: 11/08/2022]
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26
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Fürmeyer F, Münzberg D, Carrella LM, Rentschler E. First Cobalt(II) Spin Crossover Compound with N 4S 2-Donorset. Molecules 2020; 25:molecules25040855. [PMID: 32075199 PMCID: PMC7070910 DOI: 10.3390/molecules25040855] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 02/10/2020] [Accepted: 02/11/2020] [Indexed: 11/16/2022] Open
Abstract
Herein we report the synthesis and characterization of a novel bis-tridentate 1,3,4-thiadiazole ligand (L = 2,5-bis[(2-pyridylmethyl)thio]methyl-1,3,4-thiadiazole). Two new mononuclear complexes of the type [MII(L)2](ClO4)2 (with M = FeII (C1) and CoII (C2)) have been synthesized, containing the new ligand (L). In both complexes the metal centers are coordinated by an N4S2-donorset and each of the two ligands is donating to the metal ion with just one of the tridentate pockets. The iron(II) complex (C1) is in the low spin [LS] state below room temperature and shows an increase in the magnetic moment only above 300 K. In contrast, the cobalt(II) complex (C2) shows a gradual spin crossover (SCO) with T1/2 = 175 K. To our knowledge, this is the first cobalt(II) SCO complex with an N4S2-coordination.
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27
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Gueret R, Castillo CE, Rebarz M, Thomas F, Sliwa M, Chauvin J, Dautreppe B, Pécaut J, Fortage J, Collomb MN. Cobalt(II) Pentaaza-Macrocyclic Schiff Base Complex as Catalyst for Light-Driven Hydrogen Evolution in Water: Electrochemical Generation and Theoretical Investigation of the One-Electron Reduced Species. Inorg Chem 2019; 58:9043-9056. [DOI: 10.1021/acs.inorgchem.9b00447] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Robin Gueret
- Univ. Grenoble Alpes, CNRS, DCM, 38000 Grenoble, France
| | | | - Mateusz Rebarz
- Université de Lille, CNRS, UMR 8516, LASIR, Laboratoire de Spectrochimie Infrarouge et Raman, F59 000 Lille, France
| | | | - Michel Sliwa
- Université de Lille, CNRS, UMR 8516, LASIR, Laboratoire de Spectrochimie Infrarouge et Raman, F59 000 Lille, France
| | | | - Baptiste Dautreppe
- Univ. Grenoble Alpes, CNRS, DCM, 38000 Grenoble, France
- Univ. Grenoble Alpes, CEA, CNRS, IRI, SYMMES 38000 Grenoble, France
| | - Jacques Pécaut
- Univ. Grenoble Alpes, CEA, CNRS, IRI, SYMMES 38000 Grenoble, France
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28
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Rupp M, Auvray T, Rousset E, Mercier GM, Marvaud V, Kurth DG, Hanan GS. Photocatalytic Hydrogen Evolution Driven by a Heteroleptic Ruthenium(II) Bis(terpyridine) Complex. Inorg Chem 2019; 58:9127-9134. [PMID: 31247814 DOI: 10.1021/acs.inorgchem.9b00698] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Since the initial report by Lehn et al. in 1979, ruthenium tris(bipyridine) ([Ru(bpy)3]2+) and its numerous derivatives were applied as photosensitizers (PSs) in a large panel of photocatalytic conditions while the bis(terpyridine) analogues were disregarded because of their low quantum yields and short excited-state lifetimes. In this study, we prepared a new terpyridine ligand, 4'-(4-bromophenyl)-4,4‴:4″,4‴'-dipyridinyl- 2,2':6',2″-terpyridine (Bipytpy) and used it to prepare the heteroleptic complex [Ru(Tolyltpy)(Bipytpy)](PF6)2 (1; Tolyltpy = 4'-tolyl-2,2':6',2'-terpyridine). Complex 1 exhibits enhanced photophysical properties with a higher quantum yield (7.4 × 10-4) and a longer excited-state lifetime (3.8 ns) compared to those of [Ru(Tolyltpy)2](PF6)2 (3 × 10-5 and 0.74 ns, respectively). These enhanced photophysical characteristics and the potential for PS-catalyst interaction through the peripheral pyridines led us to apply the complex for visible-light-driven hydrogen evolution. The photocatalytic system based on 1 as the PS, triethanolamine as a sacrificial donor, and cobaloxime as a catalyst exhibits sustained activity over more than 10 days under blue-light irradiation (light-emitting diode centered at 450 nm). A maximum turnover number of 764 was obtained after 12 days.
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Affiliation(s)
- Mira Rupp
- Lehrstuhl für Chemische Technologie der Materialsynthese , Julius-Maximilians-Universität Würzburg , Röntgenring 11 , D-97070 Würzburg , Germany.,Département de Chimie , Université de Montréal , Montréal H3C 3J7 , Québec Canada
| | - Thomas Auvray
- Département de Chimie , Université de Montréal , Montréal H3C 3J7 , Québec Canada
| | - Elodie Rousset
- Département de Chimie , Université de Montréal , Montréal H3C 3J7 , Québec Canada.,Institut Parisien de Chimie Moléculaire , Sorbonne Université, CNRS UMR 8232 , 4 place Jussieu , 75252 Paris Cedex 05 , France
| | - Gabriel M Mercier
- Département de Chimie , Université de Montréal , Montréal H3C 3J7 , Québec Canada
| | - Valérie Marvaud
- Institut Parisien de Chimie Moléculaire , Sorbonne Université, CNRS UMR 8232 , 4 place Jussieu , 75252 Paris Cedex 05 , France
| | - Dirk G Kurth
- Lehrstuhl für Chemische Technologie der Materialsynthese , Julius-Maximilians-Universität Würzburg , Röntgenring 11 , D-97070 Würzburg , Germany
| | - Garry S Hanan
- Département de Chimie , Université de Montréal , Montréal H3C 3J7 , Québec Canada
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29
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Lu Z, Lavendomme R, Burghaus O, Nitschke JR. A Zn
4
L
6
Capsule with Enhanced Catalytic C−C Bond Formation Activity upon C
60
Binding. Angew Chem Int Ed Engl 2019; 58:9073-9077. [DOI: 10.1002/anie.201903286] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Revised: 04/20/2019] [Indexed: 11/10/2022]
Affiliation(s)
- Zhenpin Lu
- Department of ChemistryUniversity of Cambridge Lensfield Road Cambridge CB2 1EW UK
| | - Roy Lavendomme
- Department of ChemistryUniversity of Cambridge Lensfield Road Cambridge CB2 1EW UK
| | - Olaf Burghaus
- Fachbereich ChemiePhilipps-Universität Marburg Hans-Meerwein-Str. 4 35032 Marburg Germany
| | - Jonathan R. Nitschke
- Department of ChemistryUniversity of Cambridge Lensfield Road Cambridge CB2 1EW UK
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30
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Lu Z, Lavendomme R, Burghaus O, Nitschke JR. A Zn
4
L
6
Capsule with Enhanced Catalytic C−C Bond Formation Activity upon C
60
Binding. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201903286] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Zhenpin Lu
- Department of ChemistryUniversity of Cambridge Lensfield Road Cambridge CB2 1EW UK
| | - Roy Lavendomme
- Department of ChemistryUniversity of Cambridge Lensfield Road Cambridge CB2 1EW UK
| | - Olaf Burghaus
- Fachbereich ChemiePhilipps-Universität Marburg Hans-Meerwein-Str. 4 35032 Marburg Germany
| | - Jonathan R. Nitschke
- Department of ChemistryUniversity of Cambridge Lensfield Road Cambridge CB2 1EW UK
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Iyer A, Kearney K, Ertekin E. Computational Approaches to Photoelectrode Design through Molecular Functionalization for Enhanced Photoelectrochemical Water Splitting. CHEMSUSCHEM 2019; 12:1858-1871. [PMID: 30693653 DOI: 10.1002/cssc.201802514] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 12/24/2018] [Indexed: 06/09/2023]
Abstract
Photoelectrochemical water splitting is a promising carbon-free approach to produce hydrogen from water. A photoelectrochemical cell consists of a semiconductor photoelectrode in contact with an aqueous electrolyte. Its performance is sensitive to properties of the photoelectrode/electrolyte interface, which may be tuned through functionalization of the photoelectrode surface with organic molecules. This can lead to improvements in the photoelectrode's properties. This Minireview summarizes key computational investigations on using molecular functionalization to modify photoelectrode stability, barrier height, and catalytic activity. It is discussed how first-principles density functional theory, first-principles molecular dynamics, and device modeling simulations can provide predictive insights and complement experimental investigations of functionalized photoelectrodes. Challenges and future directions in the computational modeling of functionalized photoelectrode/electrolyte interfaces within the context of experimental studies are also highlighted.
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Affiliation(s)
- Ashwathi Iyer
- Department of Physics, University of Illinois at Urbana-Champaign, 1110 W Green Street, Urbana, Illinois, 61801, USA
- International Institute of Carbon Neutral Energy Research (WPI-I2CNER), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka, 819-0395, Japan
- Materials Research Laboratory, University of Illinois at Urbana-Champaign, 104 South Goodwin Avenue, Urbana, Illinois, 61801, USA
| | - Kara Kearney
- Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, 1206 W Green Street, Urbana, Illinois, 61801, USA
- International Institute of Carbon Neutral Energy Research (WPI-I2CNER), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka, 819-0395, Japan
- Materials Research Laboratory, University of Illinois at Urbana-Champaign, 104 South Goodwin Avenue, Urbana, Illinois, 61801, USA
| | - Elif Ertekin
- Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, 1206 W Green Street, Urbana, Illinois, 61801, USA
- International Institute of Carbon Neutral Energy Research (WPI-I2CNER), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka, 819-0395, Japan
- Materials Research Laboratory, University of Illinois at Urbana-Champaign, 104 South Goodwin Avenue, Urbana, Illinois, 61801, USA
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32
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Pankhurst JR, Paul S, Zhu Y, Williams CK, Love JB. Polynuclear alkoxy-zinc complexes of bowl-shaped macrocycles and their use in the copolymerisation of cyclohexene oxide and CO 2. Dalton Trans 2019; 48:4887-4893. [PMID: 30896006 DOI: 10.1039/c9dt00595a] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The reactions between alcohols and the tetranuclear ethyl-Zn complexes of an ortho-phenylene-bridged polypyrrole macrocycle, Zn4Et4(L1) 1 and the related anthracenyl-bridged macrocyclic complex, Zn4Et4(THF)4(L2) 2 have been studied. With long-chain alcohols such as n-hexanol, the clean formation of the tetranuclear hexoxide complex Zn4(OC6H13)4(L1) 3 occurs. In contrast, the use of shorter-chain alcohols such as i-propanol results in the trinuclear complex Zn3(μ2-OiPr)2(μ3-OiPr)(HL1) 4 that arises from demetalation; this complex was characterised by X-ray crystallography. The clean formation of these polynuclear zinc clusters allowed a study of their use as catalysts in the ring-opening copolymerisation (ROCOP) reaction between cyclohexene oxide and CO2. In situ reactions involving the pre-catalyst 1 and n-hexanol formed the desired polymer with the best selectivity for polycarbonate (90%) at 30 atm CO2, whilst the activity and performance of pre-catalyst 2 was poor in comparison.
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Affiliation(s)
- James R Pankhurst
- EaStCHEM School of Chemistry, The University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, UK.
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Auvray T, Sahoo R, Deschênes D, Hanan GS. Heteroleptic ruthenium bis-terpyridine complexes bearing a 4-(dimethylamino)phenyl donor and free coordination sites for hydrogen photo-evolution. Dalton Trans 2019; 48:15136-15143. [DOI: 10.1039/c9dt02613d] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Three new ruthenium bis-terpyridine complexes bearing both an internal electron donor and peripheral coordination site(s) are used as photosensitisers in H2 photo-evolution under blue and green light with sustained activity for at least two days.
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Affiliation(s)
- Thomas Auvray
- Département de Chimie
- Université de Montréal
- Montréal
- Canada
| | - Rakesh Sahoo
- Département de Chimie
- Université de Montréal
- Montréal
- Canada
| | | | - Garry S. Hanan
- Département de Chimie
- Université de Montréal
- Montréal
- Canada
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34
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Kato M, Kon K, Hirayama J, Yagi I. Host–guest chemistry between cyclodextrin and a hydrogen evolution catalyst cobaloxime. NEW J CHEM 2019. [DOI: 10.1039/c9nj00081j] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report the host–guest chemistry between cyclodextrin and a bisdimethylglyoximato cobalt complex, cobaloxime.
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Affiliation(s)
- Masaru Kato
- Section of Environmental Materials Science
- Faculty of Environmental Earth Science
- Hokkaido University
- Sapporo 060-0810
- Japan
| | - Keita Kon
- Division of Environmental Materials Science
- Graduate School of Environmental Science
- Hokkaido University
- Sapporo 060-0810
- Japan
| | - Jun Hirayama
- Division of Environmental Materials Science
- Graduate School of Environmental Science
- Hokkaido University
- Sapporo 060-0810
- Japan
| | - Ichizo Yagi
- Section of Environmental Materials Science
- Faculty of Environmental Earth Science
- Hokkaido University
- Sapporo 060-0810
- Japan
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35
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Rajak S, Schott O, Kaur P, Maris T, Hanan GS, Duong A. Mimicking 2,2′:6′,2′′:6′′,2′′′-quaterpyridine complexes for the light-driven hydrogen evolution reaction: synthesis, structural, thermal and physicochemical characterizations. RSC Adv 2019; 9:28153-28164. [PMID: 35530454 PMCID: PMC9071053 DOI: 10.1039/c9ra04303a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Accepted: 08/26/2019] [Indexed: 11/21/2022] Open
Abstract
The synthetic difficulties associated with quaterpyridine (qtpy) complexes have limited their use in the formation of various metallosupramolecular architectures in spite of their diverse structural and physicochemical properties. Providing a new facile synthetic route to the synthesis of functionalised qtpy mimics, we herein report the synthesis of three novel –NH2 functionalized qtpy-like complexes 12–14 with the general formula M(C16H14N12)(NO3)2 (M = Co(ii), Ni(ii) and Cu(ii)) in high yield and purity. Characterization of these complexes has been done by single crystal X-ray diffraction (SCXRD), thermogravimetric analysis, UV-Vis, infrared, mass spectrometry and cyclic voltammetry. As indicated by SCXRD, in all the synthesized complexes, the metal ions show a strongly distorted octahedral coordination geometry and typical hydrogen bonding networks involving DAT groups. In addition, complexes 12–14 have been analyzed as potential photocatalysts for hydrogen evolution reaction (HER) displaying good turnover numbers (TONs). Hydrogen produced from these photocatalysts can serve as the possible alternative for fossil fuels. To the best of our knowledge, this is the only study showcasing –NH2 functionalized qtpy-like complexes of Co(ii), Ni(ii) and Cu(ii) and employing them as photocatalysts for HER. Thus, a single proposed strategy solves two purposes-one related to synthesis while second is related to our environment. Facile synthesis of three novel –NH2 functionalized qtpy-like complexes, their characterizations and study of their photocatalytic properties for hydrogen evolution reaction.![]()
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Affiliation(s)
- Sanil Rajak
- Département de Chimie, Biochimie et Physique
- Institut de Recherche sur L’Hydrogène
- Université du Québec à Trois-Rivières
- Trois-Rivières
- Canada
| | - Olivier Schott
- Département de Chimie
- Université de Montréal
- Montréal
- Canada
| | - Prabhjyot Kaur
- Département de Chimie, Biochimie et Physique
- Institut de Recherche sur L’Hydrogène
- Université du Québec à Trois-Rivières
- Trois-Rivières
- Canada
| | - Thierry Maris
- Département de Chimie
- Université de Montréal
- Montréal
- Canada
| | - Garry S. Hanan
- Département de Chimie
- Université de Montréal
- Montréal
- Canada
| | - Adam Duong
- Département de Chimie, Biochimie et Physique
- Institut de Recherche sur L’Hydrogène
- Université du Québec à Trois-Rivières
- Trois-Rivières
- Canada
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36
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Wang D, Ekanayake DM, Lindeman SV, Verani CN, Fiedler AT. Multielectron Redox Chemistry of Transition Metal Complexes Supported by a Non‐Innocent N
3
P
2
Ligand: Synthesis, Characterization, and Catalytic Properties. Eur J Inorg Chem 2018. [DOI: 10.1002/ejic.201800843] [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)
- Denan Wang
- Department of Chemistry Marquette University 53201 Milwaukee Wisconsin United States
| | - Danushka M. Ekanayake
- Department of Chemistry Wayne State University 5101 Cass Ave 48202 Detroit MI United States
| | - Sergey V. Lindeman
- Department of Chemistry Marquette University 53201 Milwaukee Wisconsin United States
| | - Cláudio N. Verani
- Department of Chemistry Wayne State University 5101 Cass Ave 48202 Detroit MI United States
| | - Adam T. Fiedler
- Department of Chemistry Marquette University 53201 Milwaukee Wisconsin United States
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37
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Karabulut FNH, Feltham HLC, Brooker S. Substituents drive ligand rearrangements, giving dinuclear rather than mononuclear complexes, and tune Co II/III redox potential. Dalton Trans 2018; 47:11749-11759. [PMID: 29809223 DOI: 10.1039/c8dt01502c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Three new tetradentate imine ligands, HLHBr, HLClH and HLBrH (HLR1R2) were synthesised by 2 : 1 condensation of the appropriately n-halo substituted pyridine-2-carboxaldehyde (5-bromo-4a, 6-bromo-4b or 6-chloro-4c) with 1,3-diaminopropan-2-ol (5). Reactions of each of these three ligands with one equivalent of cobalt(ii) tetrafluoroborate resulted in the formation of three N4O2 coordinated cobalt(ii) complexes: the anticipated mononuclear complex [CoII(HLHBr)(MeOH)2](BF4)2 (1), and two unexpected dinuclear complexes, [CoII2(LBrH-BF2OMe)]2(BF4)2 (2) and [CoII2(LClH-BF2OMe)]2(BF4)2 (3). Dinuclear 2 and 3 result from complexation of cobalt(ii) to the ligands derived from the sterically demanding 6-halo substituted pyridine-2-carboxaldehydes (4b and 4c) undergoing rearrangement, reacting with MeOH and a BF4 anion, resulting in a pair of borate ester bridges between the two cobalt(ii) centres. A similar type of rearrangement is proposed for the PF6 analogues. Cyclic voltammetry in acetonitrile reveals that cobalt(ii) complexes 1-3 undergo a quasi-reversible oxidation: Em = 0.57, 0.38 and 0.29 V vs. 0.01 AgNO3/Ag, respectively. The observed Em value is tuned by the ligand, with the 6-chloro-substituent leading to the lowest Em value being observed for the corresponding cobalt complex, 3, rather than for either of the complexes of the n-bromo-substituted ligands (n = 6 or 5), 2 and 1.
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Affiliation(s)
- Fabrice N H Karabulut
- Department of Chemistry and MacDiarmid Institute of Advanced Materials and Nanotechnology, University of Otago, PO Box 56, Dunedin 9054, New Zealand.
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