1
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Malcomson T, Rummel F, Barchenko M, O'Malley P. Hey ho, where'd the proton go? Final deprotonation of O6 within the S 3 state of photosystem II. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2024; 257:112946. [PMID: 38843709 DOI: 10.1016/j.jphotobiol.2024.112946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 04/04/2024] [Accepted: 05/25/2024] [Indexed: 07/16/2024]
Abstract
The deprotonation of O6 within the S3 state marks the final deprotonation event before the formation of oxygen‑oxygen bond interactions and eventual production and release of dioxygen. Gaining a thorough understanding of this event, from the proton acceptors involved, to the exfiltration pathways available, is key in determining the nature of the resulting oxygen species, influencing the mechanism through which the first oxygen‑oxygen bond forms. Computational analysis, using BS-DFT methodologies, showed that proton abstraction by the local Glu189 residue provides consistent evidence against this being a viable mechanistic pathway due to the lack of a stable product structure. In contrast, abstraction via W3 shows an increasingly stable oxo-oxo product state between r[O5O6] = 2.1 Å & 1.9 Å. The resulting oxo-oxo state is stabilised through donation of β electron character from O6 to Mn1 and α electron character from O6 to O5. This donation from the O6 lone pair is shown to be a key factor in stabilising the oxo-oxo state, in addition to showing the initiation of first O5-O6 bond.
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Affiliation(s)
- Thomas Malcomson
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK.
| | - Felix Rummel
- Department of Chemistry, School of Natural Sciences, The University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Maxim Barchenko
- Department of Chemistry, School of Natural Sciences, The University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Patrick O'Malley
- Department of Chemistry, School of Natural Sciences, The University of Manchester, Oxford Road, Manchester M13 9PL, UK
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2
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Hernández-Fernández J, Puello-Polo E, Marquez E. Study of the Chemical Activities of Carbon Monoxide, Carbon Dioxide, and Oxygen Traces as Critical Inhibitors of Polypropylene Synthesis. Polymers (Basel) 2024; 16:605. [PMID: 38475289 DOI: 10.3390/polym16050605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 10/01/2023] [Accepted: 10/04/2023] [Indexed: 03/14/2024] Open
Abstract
This study outlines the investigation into how the compounds CO2, CO, and O2 interact with the active center of titanium (Ti) on the surface of MgCl2 and how these interactions impact the productivity of the Ziegler-Natta catalyst, ultimately influencing the thermal stability of the produced polypropylene. The calculations revealed that the adsorption energies of Ti-CO2-CO and O2 were -9.6, -12.5, and -2.32 Kcal/mol, respectively. Using the density functional theory in quantum calculations, the impacts of electronic properties and molecular structure on the adsorption of CO, O2, and CO2 on the Ziegler-Natta catalyst were thoroughly explored. Additionally, the Gibbs free energy and enthalpy of adsorption were examined. It was discovered that strong adsorption and a significant energy release (-16.2 kcal/mol) during CO adsorption could explain why this gas caused the most substantial reductions in the ZN catalyst productivity. These findings are supported by experimental tests showing that carbon monoxide has the most significant impact on the ZN catalyst productivity, followed by carbon dioxide, while oxygen exerts a less pronounced inhibitory effect.
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Affiliation(s)
- Joaquín Hernández-Fernández
- Chemistry Program, Department of Natural and Exact Sciences, University of Cartagena, San Pablo Campus, Cartagena 130015, Colombia
- Chemical Engineering Program, School of Engineering, Universidad Tecnológica de Bolivar, Parque Industrial y Tecnológico Carlos Vélez Pombo Km 1 Vía Turbaco, Cartagena 130001, Colombia
- Department of Natural and Exact Science, Universidad de la Costa, Barranquilla 080002, Colombia
| | - Esneyder Puello-Polo
- Group de Investigación en Oxi/Hidrotratamiento Catalítico Y Nuevos Materiales, Programa de Química-Ciencias Básicas, Universidad del Atlántico, Puerto Colombia 081001, Colombia
| | - Edgar Marquez
- Grupo de Investigaciones en Química Y Biología, Departamento de Química Y Biología, Facultad de Ciencias Básicas, Universidad del Norte, Carrera 51B, Km 5, Vía Puerto Colombia, Barranquilla 081007, Colombia
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3
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He X, Iliescu A, Yang T, Arguilla MQ, Chen T, Kulik HJ, Dincă M. Reversible O-O Bond Scission and O 2 Evolution at MOF-Supported Tetramanganese Clusters. J Am Chem Soc 2023. [PMID: 37471064 DOI: 10.1021/jacs.3c05374] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/21/2023]
Abstract
The scission of the O-O bond in O2 during respiration and the formation of the O-O bond during photosynthesis are the engines of aerobic life. Likewise, the reduction of O2 and the oxidation of reduced oxygen species to form O2 are indispensable components for emerging renewable technologies, including energy storage and conversion, yet discrete molecule-like systems that promote these fundamental reactions are rare. Herein, we report a square-planar tetramanganese cluster formed by self-assembly within a metal-organic framework that reversibly reduces O2 by four electrons, facilitating the interconversion between molecular O2 and metal-oxo species. The tetranuclear cluster spontaneously cleaves the O-O bond of O2 at room temperature to generate a tetramanganese-bis(μ2-oxo) species, which, in turn, is competent for O-O bond reformation and O2 evolution at elevated temperatures, enabled by the head-to-head orientation of two oxo species. This study demonstrates the viability of four-electron interconversion between molecular O2 and metal-oxo species and highlights the importance of site isolation for achieving multi-electron chemistry at polynuclear metal clusters.
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Affiliation(s)
- Xin He
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Andrei Iliescu
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Tzuhsiung Yang
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Maxx Q Arguilla
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Tianyang Chen
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Heather J Kulik
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Mircea Dincă
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
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4
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Tretiakov S, Lutz M, Titus CJ, de Groot F, Nehrkorn J, Lohmiller T, Holldack K, Schnegg A, Tarrago MFX, Zhang P, Ye S, Aleshin D, Pavlov A, Novikov V, Moret ME. Homoleptic Fe(III) and Fe(IV) Complexes of a Dianionic C 3-Symmetric Scorpionate. Inorg Chem 2023. [PMID: 37369076 DOI: 10.1021/acs.inorgchem.3c00871] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/29/2023]
Abstract
High-valent iron species have been implicated as key intermediates in catalytic oxidation reactions, both in biological and synthetic systems. Many heteroleptic Fe(IV) complexes have now been prepared and characterized, especially using strongly π-donating oxo, imido, or nitrido ligands. On the other hand, homoleptic examples are scarce. Herein, we investigate the redox chemistry of iron complexes of the dianonic tris-skatylmethylphosphonium (TSMP2-) scorpionate ligand. One-electron oxidation of the tetrahedral, bis-ligated [(TSMP)2FeII]2- leads to the octahedral [(TSMP)2FeIII]-. The latter undergoes thermal spin-cross-over both in the solid state and solution, which we characterize using superconducting quantum inference device (SQUID), Evans method, and paramagnetic nuclear magnetic resonance spectroscopy. Furthermore, [(TSMP)2FeIII]- can be reversibly oxidized to the stable high-valent [(TSMP)2FeIV]0 complex. We use a variety of electrochemical, spectroscopic, and computational techniques as well as SQUID magnetometry to establish a triplet (S = 1) ground state with a metal-centered oxidation and little spin delocalization on the ligand. The complex also has a fairly isotropic g-tensor (giso = 1.97) combined with a positive zero-field splitting (ZFS) parameter D (+19.1 cm-1) and very low rhombicity, in agreement with quantum chemical calculations. This thorough spectroscopic characterization contributes to a general understanding of octahedral Fe(IV) complexes.
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Affiliation(s)
- Serhii Tretiakov
- Organic Chemistry & Catalysis, Institute for Sustainable and Circular Chemistry, Utrecht University, 3584 CG Utrecht, The Netherlands
| | - Martin Lutz
- Structural Biochemistry, Bijvoet Centre for Biomolecular Research, Faculty of Science, Utrecht University, 3584 CG Utrecht, The Netherlands
| | - Charles James Titus
- Department of Physics, Stanford University, Stanford, California 94305, United States
| | - Frank de Groot
- Materials Chemistry & Catalysis, Debye Institute for Materials Science, Utrecht University, 3584 CG Utrecht, The Netherlands
| | - Joscha Nehrkorn
- Max-Planck-Institute for Chemical Energy Conversion, EPR Research Group, 45470 Mülheim/Ruhr, Germany
| | - Thomas Lohmiller
- Department Spins in Energy Conversion and Quantum Information Science, Helmholtz Zentrum Berlin für Materialien und Energie GmbH, EPR4 Energy Joint Lab, 12489 Berlin, Germany
| | - Karsten Holldack
- Department of Optics and Beamlines, Helmholtz Zentrum Berlin für Materialien und Energie GmbH, 12489 Berlin, Germany
| | - Alexander Schnegg
- Max-Planck-Institute for Chemical Energy Conversion, EPR Research Group, 45470 Mülheim/Ruhr, Germany
| | | | - Peng Zhang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
- University of Chinese Academy of Sciences, Beijing 10049, China
| | - Shengfa Ye
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Dmitry Aleshin
- A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova Street 28, Moscow 119991, Russia
| | - Alexander Pavlov
- A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova Street 28, Moscow 119991, Russia
- Moscow Institute of Physics and Technology, Institutskiy per., 9, Dolgoprudny, Moscow 119991, Russia
| | - Valentin Novikov
- Moscow Institute of Physics and Technology, Institutskiy per., 9, Dolgoprudny, Moscow 119991, Russia
| | - Marc-Etienne Moret
- Organic Chemistry & Catalysis, Institute for Sustainable and Circular Chemistry, Utrecht University, 3584 CG Utrecht, The Netherlands
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5
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Wen H, Zhang S, Yu T, Yi Z, Guo R. ZIF-67-based catalysts for oxygen evolution reaction. NANOSCALE 2021; 13:12058-12087. [PMID: 34231644 DOI: 10.1039/d1nr01669e] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
As a new type of crystalline porous material, the imidazole zeolite framework (ZIF) has attracted widespread attention due to its ultra-high surface area, large pore volume, and unique advantage of easy functionalization. Developing different methods to control the shape and composition of ZIF is very important for its practical application as catalyst. In recent years, nano-ZIF has been considered an electrode material with excellent oxygen evolution reaction (OER) performance, which provides a new way to research electrolyzed water. This review focuses on the morphological engineering of the original ZIF-67 and its derivatives (core-shell, hollow, and array structures) through doping (cation doping, anion doping, and co-doping), derivative composition engineering (metal oxide, phosphide, sulfide, selenide, and telluride), and the corresponding single-atom catalysis. Besides, combined with DFT calculations, it emphasizes the in-depth understanding of actual active sites and provides insights into the internal mechanism of enhancing the OER and proposes the challenges and prospects of ZIF-67 based electrocatalysts. We summarize the application of ZIF-67 and its derivatives in the OER for the first time, which has significantly guided research in this field.
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Affiliation(s)
- Hui Wen
- School of Materials Science and Engineering, Northeastern University, Shenyang 110819, China.
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6
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Panda C, Sarkar A, Sen Gupta S. Coordination chemistry of carboxamide ‘Nx’ ligands to metal ions for bio-inspired catalysis. Coord Chem Rev 2020. [DOI: 10.1016/j.ccr.2020.213314] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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7
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Krewald V, Neese F, Pantazis DA. Implications of structural heterogeneity for the electronic structure of the final oxygen-evolving intermediate in photosystem II. J Inorg Biochem 2019; 199:110797. [PMID: 31404888 DOI: 10.1016/j.jinorgbio.2019.110797] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 07/18/2019] [Accepted: 08/01/2019] [Indexed: 10/26/2022]
Abstract
Heterogeneity in intermediate catalytic states of the oxygen-evolving complex (OEC) of Photosystem II is known from a wide range of experimental and theoretical data, but its potential implications for the mechanism of water oxidation remain unexplored. We delineate the consequences of structural heterogeneity for the final step of the catalytic cycle by tracing the evolution of three spectroscopically relevant and structurally distinct components of the last metastable S3 state to the transient O2-evolving S4 state of the OEC. Using quantum chemical calculations, we show that each S3 isomer leads to a different electronic structure formulation for the active S4 state. Crucially, in addition to previously hypothesized Mn(IV)-oxyl species, we establish for the first time, how a genuine Mn(V)-oxo can be obtained in the catalytically active S4 state: this takes the form of a five-coordinate and locally high-spin (SMn = 1) Mn(V) site. This formulation for the S4 state evolves naturally from a preceding S3-state structural intermediate that contains a quasi-trigonal-bipyramidal Mn(IV) ion. The results strongly suggest that water binding in the S3 state is not prerequisite for reaching the oxygen-evolving S4 state of the complex, supporting the notion that both substrates are preloaded at the beginning of the catalytic cycle. This scenario allows true four-electron metal-centered hole accumulation to precede OO bond formation and hence the latter can proceed via a genuine even-electron mechanism. This can occur as intramolecular nucleophilic coupling of two oxo units synchronously with the binding of a water substrate for the next catalytic cycle.
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Affiliation(s)
- Vera Krewald
- Theoretische Chemie, Fachbereich Chemie, Technische Universität Darmstadt, Alarich-Weiss-Str. 4, 64287 Darmstadt, Germany
| | - Frank Neese
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Dimitrios A Pantazis
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
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8
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Nandy A, Zhu J, Janet JP, Duan C, Getman RB, Kulik HJ. Machine Learning Accelerates the Discovery of Design Rules and Exceptions in Stable Metal–Oxo Intermediate Formation. ACS Catal 2019. [DOI: 10.1021/acscatal.9b02165] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
| | - Jiazhou Zhu
- Department of Chemical & Biomolecular Engineering, Clemson University, Clemson, South Carolina 29634, United States
| | | | | | - Rachel B. Getman
- Department of Chemical & Biomolecular Engineering, Clemson University, Clemson, South Carolina 29634, United States
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9
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Lloret-Fillol J, Costas M. Water oxidation at base metal molecular catalysts. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2019. [DOI: 10.1016/bs.adomc.2019.02.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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10
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Cheng J, Wang L, Wang P, Deng L. High-Oxidation-State 3d Metal (Ti-Cu) Complexes with N-Heterocyclic Carbene Ligation. Chem Rev 2018; 118:9930-9987. [PMID: 30011189 DOI: 10.1021/acs.chemrev.8b00096] [Citation(s) in RCA: 109] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
High-oxidation-state 3d metal species have found a wide range of applications in modern synthetic chemistry and materials science. They are also implicated as key reactive species in biological reactions. These applications have thus prompted explorations of their formation, structure, and properties. While the traditional wisdom regarding these species was gained mainly from complexes supported by nitrogen- and oxygen-donor ligands, recent studies with N-heterocyclic carbenes (NHCs), which are widely used for the preparation of low-oxidation-state transition metal complexes in organometallic chemistry, have led to the preparation of a large variety of isolable high-oxidation-state 3d metal complexes with NHC ligation. Since the first report in this area in the 1990s, isolable complexes of this type have been reported for titanium(IV), vanadium(IV,V), chromium(IV,V), manganese(IV,V), iron(III,IV,V), cobalt(III,IV,V), nickel(IV), and copper(II). With the aim of providing an overview of this intriguing field, this Review summarizes our current understanding of the synthetic methods, structure and spectroscopic features, reactivity, and catalytic applications of high-oxidation-state 3d metal NHC complexes of titanium to copper. In addition to this progress, factors affecting the stability and reactivity of high-oxidation-state 3d metal NHC species are also presented, as well as perspectives on future efforts.
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Affiliation(s)
- Jun Cheng
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , People's Republic of China
| | - Lijun Wang
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , People's Republic of China
| | - Peng Wang
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , People's Republic of China
| | - Liang Deng
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , People's Republic of China
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11
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Halbach RL, Gygi D, Bloch ED, Anderson BL, Nocera DG. Structurally characterized terminal manganese(iv) oxo tris(alkoxide) complex. Chem Sci 2018; 9:4524-4528. [PMID: 29896395 PMCID: PMC5958342 DOI: 10.1039/c8sc01164h] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 04/16/2018] [Indexed: 12/22/2022] Open
Abstract
First structurally characterized Mn(iv) oxo.
A Mn(iv) complex featuring a terminal oxo ligand, [MnIV(O)(ditox)3][K(15-C-5)2] (3; ditox = tBu2MeCO–, 15-C-5 = 15-crown-5-ether) has been isolated and structurally characterized. Treatment of the colorless precursor [MnII(ditox)3][K(15-C-5)2] (2) with iodosobenzene affords 3 as a green free-flowing powder in high yields. The X-ray crystal structure of 3 reveals a pseudotetrahedral geometry about the central Mn, which features a terminal oxo (d(Mn–Oterm = 1.628(2) Å)). EPR spectroscopy, SQUID magnetometry, and Evans method magnetic susceptibility indicate that 3 consists of a high-spin S = 3/2 Mn(iv) metal center. 3 promotes C–H bond activation by a hydrogen atom abstraction. The [MnIV(O)(ditox)3]– furnishes a model for the proposed terminal oxo of the unique manganese of the oxygen evolving complex of photosystem II.
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Affiliation(s)
- Robert L Halbach
- Department of Chemistry and Chemical Biology , Harvard University , Cambridge , Massachusetts 02138 , USA .
| | - David Gygi
- Department of Chemistry and Chemical Biology , Harvard University , Cambridge , Massachusetts 02138 , USA .
| | - Eric D Bloch
- Department of Chemistry and Chemical Biology , Harvard University , Cambridge , Massachusetts 02138 , USA .
| | - Bryce L Anderson
- Department of Chemistry and Chemical Biology , Harvard University , Cambridge , Massachusetts 02138 , USA .
| | - Daniel G Nocera
- Department of Chemistry and Chemical Biology , Harvard University , Cambridge , Massachusetts 02138 , USA .
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12
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Huynh M, Ozel T, Liu C, Lau EC, Nocera DG. Design of template-stabilized active and earth-abundant oxygen evolution catalysts in acid. Chem Sci 2017; 8:4779-4794. [PMID: 29163926 PMCID: PMC5637126 DOI: 10.1039/c7sc01239j] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2017] [Accepted: 05/05/2017] [Indexed: 12/24/2022] Open
Abstract
Oxygen evolution reaction (OER) catalysts that are earth-abundant and are active and stable in acid are unknown. Active catalysts derived from Co and Ni oxides dissolve at low pH, whereas acid stable systems such as Mn oxides (MnO x ) display poor OER activity. We now demonstrate a rational approach for the design of earth-abundant catalysts that are stable and active in acid by treating activity and stability as decoupled elements of mixed metal oxides. Manganese serves as a stabilizing structural element for catalytically active Co centers in CoMnO x films. In acidic solutions (pH 2.5), CoMnO x exhibits the OER activity of electrodeposited Co oxide (CoO x ) with a Tafel slope of 70-80 mV per decade while also retaining the long-term acid stability of MnO x films for OER at 0.1 mA cm-2. Driving OER at greater current densities in this system is not viable because at high anodic potentials, Mn oxides convert to and dissolve as permanganate. However, by exploiting the decoupled design of the catalyst, the stabilizing structural element may be optimized independently of the Co active sites. By screening potential-pH diagrams, we replaced Mn with Pb to prepare CoFePbO x films that maintained the high OER activity of CoO x at pH 2.5 while exhibiting long-term acid stability at higher current densities (at 1 mA cm-2 for over 50 h at pH 2.0). Under these acidic conditions, CoFePbO x exhibits OER activity that approaches noble metal oxides, thus establishing the viability of decoupling functionality in mixed metal catalysts for designing active, acid-stable, and earth-abundant OER catalysts.
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Affiliation(s)
- Michael Huynh
- Department of Chemistry and Chemical Biology , Harvard University , Cambridge , Massachusetts 02138 , USA .
| | - Tuncay Ozel
- Department of Chemistry and Chemical Biology , Harvard University , Cambridge , Massachusetts 02138 , USA .
| | - Chong Liu
- Department of Chemistry and Chemical Biology , Harvard University , Cambridge , Massachusetts 02138 , USA .
| | - Eric C Lau
- Department of Chemistry and Chemical Biology , Harvard University , Cambridge , Massachusetts 02138 , USA .
| | - Daniel G Nocera
- Department of Chemistry and Chemical Biology , Harvard University , Cambridge , Massachusetts 02138 , USA .
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13
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Jin K, Seo H, Hayashi T, Balamurugan M, Jeong D, Go YK, Hong JS, Cho KH, Kakizaki H, Bonnet-Mercier N, Kim MG, Kim SH, Nakamura R, Nam KT. Mechanistic Investigation of Water Oxidation Catalyzed by Uniform, Assembled MnO Nanoparticles. J Am Chem Soc 2017; 139:2277-2285. [PMID: 28029792 DOI: 10.1021/jacs.6b10657] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The development of active water oxidation catalysts is critical to achieve high efficiency in overall water splitting. Recently, sub-10 nm-sized monodispersed partially oxidized manganese oxide nanoparticles were shown to exhibit not only superior catalytic performance for oxygen evolution, but also unique electrokinetics, as compared to their bulk counterparts. In the present work, the water-oxidizing mechanism of partially oxidized MnO nanoparticles was investigated using integrated in situ spectroscopic and electrokinetic analyses. We successfully demonstrated that, in contrast to previously reported manganese (Mn)-based catalysts, Mn(III) species are stably generated on the surface of MnO nanoparticles via a proton-coupled electron transfer pathway. Furthermore, we confirmed as to MnO nanoparticles that the one-electron oxidation step from Mn(II) to Mn(III) is no longer the rate-determining step for water oxidation and that Mn(IV)═O species are generated as reaction intermediates during catalysis.
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Affiliation(s)
- Kyoungsuk Jin
- Department of Materials Science and Engineering, Seoul National University , Seoul 151-742, Korea
| | - Hongmin Seo
- Department of Materials Science and Engineering, Seoul National University , Seoul 151-742, Korea
| | - Toru Hayashi
- Department of Applied Chemistry, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.,Biofunctional Catalyst Research Team, RIKEN Center for Sustainable Resource Science (CSRS) , 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Mani Balamurugan
- Department of Materials Science and Engineering, Seoul National University , Seoul 151-742, Korea
| | - Donghyuk Jeong
- Western Seoul Center, Korea Basic Science Institute (KBSI) , 150, Bukahyeon-ro, Seodaemun-gu, Seoul 120-140, Korea
| | - Yoo Kyung Go
- Western Seoul Center, Korea Basic Science Institute (KBSI) , 150, Bukahyeon-ro, Seodaemun-gu, Seoul 120-140, Korea
| | - Jung Sug Hong
- Department of Materials Science and Engineering, Seoul National University , Seoul 151-742, Korea
| | - Kang Hee Cho
- Department of Materials Science and Engineering, Seoul National University , Seoul 151-742, Korea
| | - Hirotaka Kakizaki
- Department of Applied Chemistry, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.,Biofunctional Catalyst Research Team, RIKEN Center for Sustainable Resource Science (CSRS) , 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Nadège Bonnet-Mercier
- Biofunctional Catalyst Research Team, RIKEN Center for Sustainable Resource Science (CSRS) , 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Min Gyu Kim
- Pohang Accelerator Laboratory, Pohang University of Science and Technology (POSTECH) , Pohang 790-784, Korea
| | - Sun Hee Kim
- Western Seoul Center, Korea Basic Science Institute (KBSI) , 150, Bukahyeon-ro, Seodaemun-gu, Seoul 120-140, Korea
| | - Ryuhei Nakamura
- Biofunctional Catalyst Research Team, RIKEN Center for Sustainable Resource Science (CSRS) , 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Ki Tae Nam
- Department of Materials Science and Engineering, Seoul National University , Seoul 151-742, Korea
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14
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Zaharieva I, Chernev P, Berggren G, Anderlund M, Styring S, Dau H, Haumann M. Room-Temperature Energy-Sampling Kβ X-ray Emission Spectroscopy of the Mn4Ca Complex of Photosynthesis Reveals Three Manganese-Centered Oxidation Steps and Suggests a Coordination Change Prior to O2 Formation. Biochemistry 2016; 55:4197-211. [PMID: 27377097 DOI: 10.1021/acs.biochem.6b00491] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
In oxygenic photosynthesis, water is oxidized and dioxygen is produced at a Mn4Ca complex bound to the proteins of photosystem II (PSII). Valence and coordination changes in its catalytic S-state cycle are of great interest. In room-temperature (in situ) experiments, time-resolved energy-sampling X-ray emission spectroscopy of the Mn Kβ1,3 line after laser-flash excitation of PSII membrane particles was applied to characterize the redox transitions in the S-state cycle. The Kβ1,3 line energies suggest a high-valence configuration of the Mn4Ca complex with Mn(III)3Mn(IV) in S0, Mn(III)2Mn(IV)2 in S1, Mn(III)Mn(IV)3 in S2, and Mn(IV)4 in S3 and, thus, manganese oxidation in each of the three accessible oxidizing transitions of the water-oxidizing complex. There are no indications of formation of a ligand radical, thus rendering partial water oxidation before reaching the S4 state unlikely. The difference spectra of both manganese Kβ1,3 emission and K-edge X-ray absorption display different shapes for Mn(III) oxidation in the S2 → S3 transition when compared to Mn(III) oxidation in the S1 → S2 transition. Comparison to spectra of manganese compounds with known structures and oxidation states and varying metal coordination environments suggests a change in the manganese ligand environment in the S2 → S3 transition, which could be oxidation of five-coordinated Mn(III) to six-coordinated Mn(IV). Conceivable options for the rearrangement of (substrate) water species and metal-ligand bonding patterns at the Mn4Ca complex in the S2 → S3 transition are discussed.
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Affiliation(s)
- Ivelina Zaharieva
- Freie Universität Berlin , Department of Physics, 14195 Berlin, Germany
| | - Petko Chernev
- Freie Universität Berlin , Department of Physics, 14195 Berlin, Germany
| | - Gustav Berggren
- Uppsala University , Department of Chemistry, Ångström Laboratory, 75120 Uppsala, Sweden
| | - Magnus Anderlund
- Uppsala University , Department of Chemistry, Ångström Laboratory, 75120 Uppsala, Sweden
| | - Stenbjörn Styring
- Uppsala University , Department of Chemistry, Ångström Laboratory, 75120 Uppsala, Sweden
| | - Holger Dau
- Freie Universität Berlin , Department of Physics, 14195 Berlin, Germany
| | - Michael Haumann
- Freie Universität Berlin , Department of Physics, 14195 Berlin, Germany
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15
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Hodel FH, Luber S. What Influences the Water Oxidation Activity of a Bioinspired Molecular CoII4O4 Cubane? An In-Depth Exploration of Catalytic Pathways. ACS Catal 2016. [DOI: 10.1021/acscatal.5b02507] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Florian H. Hodel
- Department
of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Sandra Luber
- Department
of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
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16
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Ure AD, Lázaro IA, Cotter M, McDonald AR. Synthesis and characterisation of a mesocyclic tripodal triamine ligand. Org Biomol Chem 2016; 14:483-494. [DOI: 10.1039/c5ob01556a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The preparation and characterisation of mesocyclic polydentate amine ligands is described. The novel tridentate ligands will be employed in the stabilisation of highly reactive high-valent oxidants.
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Affiliation(s)
- Andrew D. Ure
- School of Chemistry and CRANN/AMBER Nanoscience Institute
- Trinity College Dublin
- The University of Dublin
- College Green
- Dublin 2
| | - Isabel Abánades Lázaro
- School of Chemistry and CRANN/AMBER Nanoscience Institute
- Trinity College Dublin
- The University of Dublin
- College Green
- Dublin 2
| | - Michelle Cotter
- School of Chemistry and CRANN/AMBER Nanoscience Institute
- Trinity College Dublin
- The University of Dublin
- College Green
- Dublin 2
| | - Aidan R. McDonald
- School of Chemistry and CRANN/AMBER Nanoscience Institute
- Trinity College Dublin
- The University of Dublin
- College Green
- Dublin 2
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17
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Fielden J, Sumliner JM, Han N, Geletii YV, Xiang X, Musaev DG, Lian T, Hill CL. Water splitting with polyoxometalate-treated photoanodes: enhancing performance through sensitizer design. Chem Sci 2015; 6:5531-5543. [PMID: 29861891 PMCID: PMC5949860 DOI: 10.1039/c5sc01439e] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 06/10/2015] [Indexed: 01/22/2023] Open
Abstract
Visible light driven water oxidation has been demonstrated at near-neutral pH using photoanodes based on nanoporous films of TiO2, polyoxometalate (POM) water oxidation catalyst [{Ru4O4(OH)2(H2O)4}(γ-SiW10O36)2]10- (1), and both known photosensitizer [Ru(bpy)2(H4dpbpy)]2+ (P2) and the novel crown ether functionalized dye [Ru(5-crownphen)2(H2dpbpy)](H22). Both triads, containing catalyst 1, and catalyst-free dyads, produce O2 with high faradaic efficiencies (80 to 94%), but presence of catalyst enhances quantum yield by up to 190% (maximum 0.39%). New sensitizer H22 absorbs light more strongly than P2, and increases O2 quantum yields by up to 270%. TiO2-2 based photoelectrodes are also more stable to desorption of active species than TiO2-P2: losses of catalyst 1 are halved when pH > TiO2 point-of-zero charge (pzc), and losses of sensitizer reduced below the pzc (no catalyst is lost when pH < pzc). For the triads, quantum yields of O2 are higher at pH 5.8 than at pH 7.2, opposing the trend observed for 1 under homogeneous conditions. This is ascribed to lower stability of the dye oxidized states at higher pH, and less efficient electron transfer to TiO2, and is also consistent with the 4th1-to-dye electron transfer limiting performance rather than catalyst TOFmax. Transient absorption reveals that TiO2-2-1 has similar 1st electron transfer dynamics to TiO2-P2-1, with rapid (ps timescale) formation of long-lived TiO2(e-)-2-1(h+) charge separated states, and demonstrates that metallation of the crown ether groups (Na+/Mg2+) has little or no effect on electron transfer from 1 to 2. The most widely relevant findings of this study are therefore: (i) increased dye extinction coefficients and binding stability significantly improve performance in dye-sensitized water splitting systems; (ii) binding of POMs to electrode surfaces can be stabilized through use of recognition groups; (iii) the optimal homogeneous and TiO2-bound operating pHs of a catalyst may not be the same; and (iv) dye-sensitized TiO2 can oxidize water without a catalyst.
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Affiliation(s)
- John Fielden
- Department of Chemistry , Cherry L. Emerson Center for Scientific Computation , Emory University , Atlanta , GA 30322 , USA . .,WestCHEM , School of Chemistry , University of Glasgow , G12 8QQ , UK
| | - Jordan M Sumliner
- Department of Chemistry , Cherry L. Emerson Center for Scientific Computation , Emory University , Atlanta , GA 30322 , USA .
| | - Nannan Han
- Department of Chemistry , Cherry L. Emerson Center for Scientific Computation , Emory University , Atlanta , GA 30322 , USA .
| | - Yurii V Geletii
- Department of Chemistry , Cherry L. Emerson Center for Scientific Computation , Emory University , Atlanta , GA 30322 , USA .
| | - Xu Xiang
- Department of Chemistry , Cherry L. Emerson Center for Scientific Computation , Emory University , Atlanta , GA 30322 , USA . .,State Key Laboratory of Chemical Resource Engineering , Beijing University of Chemical Technology , Beijing 1000029 , P. R. China
| | - Djamaladdin G Musaev
- Department of Chemistry , Cherry L. Emerson Center for Scientific Computation , Emory University , Atlanta , GA 30322 , USA .
| | - Tianquan Lian
- Department of Chemistry , Cherry L. Emerson Center for Scientific Computation , Emory University , Atlanta , GA 30322 , USA .
| | - Craig L Hill
- Department of Chemistry , Cherry L. Emerson Center for Scientific Computation , Emory University , Atlanta , GA 30322 , USA .
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18
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Abstract
Direct solar-to-fuels conversion can be achieved by coupling a photovoltaic device with water-splitting catalysts. We demonstrate that a solar-to-fuels efficiency (SFE) > 10% can be achieved with nonprecious, low-cost, and commercially ready materials. We present a systems design of a modular photovoltaic (PV)-electrochemical device comprising a crystalline silicon PV minimodule and low-cost hydrogen-evolution reaction and oxygen-evolution reaction catalysts, without power electronics. This approach allows for facile optimization en route to addressing lower-cost devices relying on crystalline silicon at high SFEs for direct solar-to-fuels conversion.
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19
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Codola Z, Lloret-Fillol J, Costas M. Aminopyridine Iron and Manganese Complexes as Molecular Catalysts for Challenging Oxidative Transformations. PROGRESS IN INORGANIC CHEMISTRY: VOLUME 59 2014. [DOI: 10.1002/9781118869994.ch07] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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20
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Glyoxylate as a reducing agent for manganese(III) in salen scaffold: A kinetics and mechanistic study. J CHEM SCI 2014. [DOI: 10.1007/s12039-014-0605-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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21
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Kar AK, Acharya AN, Mundlapati VR, Pradhan GC, Biswal HS, Dash AC. Ligand substitution and electron transfer reactions of trans-(diaqua)(salen)manganese(iii) with oxalate: an experimental and computational study. RSC Adv 2014. [DOI: 10.1039/c4ra10324f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
MnIII(salen)(OH2)2+ undergoes reversible anation by HOX−via Ia mechanism followed by proton controlled electron transfer involving MnIII(salen)(HOX) and H2OX.
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Affiliation(s)
- Akshaya K. Kar
- Department of Chemistry Utkal University
- Bhubaneswar 751004, India
| | - Achyut N. Acharya
- Department of Chemistry
- College of Engineering and Technology
- Bhubaneswar 751003, India
| | - V. Rao Mundlapati
- School of Chemical Sciences
- National Institute of Science Education and Research (NISER)
- Institute of Physics Campus
- Bhubaneswar 751 005, India
| | - Guru C. Pradhan
- Department of Chemistry Utkal University
- Bhubaneswar 751004, India
| | - Himansu S. Biswal
- School of Chemical Sciences
- National Institute of Science Education and Research (NISER)
- Institute of Physics Campus
- Bhubaneswar 751 005, India
| | - Anadi C. Dash
- Department of Chemistry Utkal University
- Bhubaneswar 751004, India
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22
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Naidu B, Gupta U, Maitra U, Rao C. Visible light induced oxidation of water by rare earth manganites, cobaltites and related oxides. Chem Phys Lett 2014. [DOI: 10.1016/j.cplett.2013.10.089] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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23
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Yamaguchi K, Shoji M, Isobe H, Kitagawa Y, Yamada S, Kawakami T, Yamanaka S, Okumura M. Theory of chemical bonds in metalloenzymes XVI. Oxygen activation by high-valent transition metal ions in native and artificial systems. Polyhedron 2013. [DOI: 10.1016/j.poly.2013.05.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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24
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Smeltz JL, Lilly CP, Boyle PD, Ison EA. The electronic nature of terminal oxo ligands in transition-metal complexes: ambiphilic reactivity of oxorhenium species. J Am Chem Soc 2013; 135:9433-41. [PMID: 23725588 DOI: 10.1021/ja401390v] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The synthesis of the Lewis acid-base adducts of B(C6F5)3 and BF3 with [DAAmRe(O)(X)] DAAm = N,N-bis(2-arylaminoethyl)methylamine; aryl = C6F5 (X = Me, 1, COCH3, 2, Cl, 3) as well as their diamidopyridine (DAP) (DAP=(2,6-bis((mesitylamino)methyl)pyridine) analogues, [DAPRe(O)(X)] (X = Me, 4, Cl, 5, I, 6, and COCH3,7), are described. In these complexes the terminal oxo ligands act as nucleophiles. In addition we also show that stoichiometric reactions between 3 and triarylphosphine (PAr3) result in the formation of triarylphosphine oxide (OPAr3). The electronic dependence of this reaction was studied by comparing the rates of oxygen atom transfer for various para-substituted triaryl phosphines in the presence of CO. From these experiments a reaction constant ρ = -0.29 was obtained from the Hammett plot. This suggests that the oxygen atom transfer reaction is consistent with nucleophilic attack of phosphorus on an electrophilic metal oxo. To the best of our knowledge, these are the first examples of mono-oxo d(2) metal complexes in which the oxo ligand exhibits ambiphilic reactivity.
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Affiliation(s)
- Jessica L Smeltz
- Department of Chemistry, North Carolina State University, 2620 Yarbrough Drive, Raleigh, North Carolina 27695-8204, United States
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25
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Farrow CL, Bediako DK, Surendranath Y, Nocera DG, Billinge SJL. Intermediate-Range Structure of Self-Assembled Cobalt-Based Oxygen-Evolving Catalyst. J Am Chem Soc 2013; 135:6403-6. [DOI: 10.1021/ja401276f] [Citation(s) in RCA: 139] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Christopher L. Farrow
- Department of Applied Physics
and Applied Mathematics, Columbia University, New York, New York 10027, United States
| | - D. Kwabena Bediako
- Department of Chemistry and
Chemical Biology, Harvard University, Cambridge,
Massachusetts 02138, United States
| | - Yogesh Surendranath
- Department of Chemistry and
Chemical Biology, Harvard University, Cambridge,
Massachusetts 02138, United States
| | - Daniel G. Nocera
- Department of Chemistry and
Chemical Biology, Harvard University, Cambridge,
Massachusetts 02138, United States
| | - Simon J. L. Billinge
- Department of Applied Physics
and Applied Mathematics, Columbia University, New York, New York 10027, United States
- Condensed Matter Physics and Materials
Science Department, Brookhaven National Laboratory, Upton, New York 11973, United States
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26
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Coggins MK, Martin-Diaconescu V, DeBeer S, Kovacs JA. Correlation between structural, spectroscopic, and reactivity properties within a series of structurally analogous metastable manganese(III)-alkylperoxo complexes. J Am Chem Soc 2013; 135:4260-72. [PMID: 23432090 PMCID: PMC3740743 DOI: 10.1021/ja308915x] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Manganese-peroxos are proposed as key intermediates in a number of important biochemical and synthetic transformations. Our understanding of the structural, spectroscopic, and reactivity properties of these metastable species is limited, however, and correlations between these properties have yet to be established experimentally. Herein we report the crystallographic structures of a series of structurally related metastable Mn(III)-OOR compounds, and examine their spectroscopic and reactivity properties. The four reported Mn(III)-OOR compounds extend the number of known end-on Mn(III)-(η(1)-peroxos) to six. The ligand backbone is shown to alter the metal-ligand distances and modulate the electronic properties key to bonding and activation of the peroxo. The mechanism of thermal decay of these metastable species is examined via variable-temperature kinetics. Strong correlations between structural (O-O and Mn···N(py,quin) distances), spectroscopic (E(πv*(O-O) → Mn CT band), ν(O-O)), and kinetic (ΔH(‡) and ΔS(‡)) parameters for these complexes provide compelling evidence for rate-limiting O-O bond cleavage. Products identified in the final reaction mixtures of Mn(III)-OOR decay are consistent with homolytic O-O bond scission. The N-heterocyclic amines and ligand backbone (Et vs Pr) are found to modulate structural and reactivity properties, and O-O bond activation is shown, both experimentally and theoretically, to track with metal ion Lewis acidity. The peroxo O-O bond is shown to gradually become more activated as the N-heterocyclic amines move closer to the metal ion causing a decrease in π-donation from the peroxo πv*(O-O) orbital. The reported work represents one of very few examples of experimentally verified relationships between structure and function.
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Affiliation(s)
- Michael K Coggins
- The Department of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700, USA
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27
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Wang QQ, Begum RA, Day VW, Bowman-James K. Alfred Werner’s expanded legacy: Anion and metal ion coordination in an unsymmetrical, octaamido cryptand. Polyhedron 2013. [DOI: 10.1016/j.poly.2012.08.042] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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28
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Lee CH, Lutterman DA, Nocera DG. Photoactivation of metal–halogen bonds in a Ni(ii) NHC complex. Dalton Trans 2013; 42:2355-7. [DOI: 10.1039/c2dt32885b] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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29
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Lv H, Rudd JA, Zhuk PF, Lee JY, Constable EC, Housecroft CE, Hill CL, Musaev DG, Geletii YV. Bis(4′-(4-pyridyl)-2,2′:6′,2′′-terpyridine)ruthenium(ii) complexes and their N-alkylated derivatives in catalytic light-driven water oxidation. RSC Adv 2013. [DOI: 10.1039/c3ra44192j] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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30
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Hofbauer S, Bellei M, Sündermann A, Pirker KF, Hagmüller A, Mlynek G, Kostan J, Daims H, Furtmüller PG, Djinović-Carugo K, Oostenbrink C, Battistuzzi G, Obinger C. Redox thermodynamics of high-spin and low-spin forms of chlorite dismutases with diverse subunit and oligomeric structures. Biochemistry 2012; 51:9501-12. [PMID: 23126649 PMCID: PMC3557923 DOI: 10.1021/bi3013033] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Chlorite dismutases (Clds) are heme b-containing
oxidoreductases that convert chlorite to chloride and dioxygen. In
this work, the thermodynamics of the one-electron reduction of the
ferric high-spin forms and of the six-coordinate low-spin cyanide
adducts of the enzymes from Nitrobacter winogradskyi (NwCld) and Candidatus “Nitrospira defluvii”
(NdCld) were determined through spectroelectrochemical experiments.
These proteins belong to two phylogenetically separated lineages that
differ in subunit (21.5 and 26 kDa, respectively) and oligomeric (dimeric
and pentameric, respectively) structure but exhibit similar chlorite
degradation activity. The E°′ values
for free and cyanide-bound proteins were determined to be −119
and −397 mV for NwCld and −113 and −404 mV for
NdCld, respectively (pH 7.0, 25 °C). Variable-temperature spectroelectrochemical
experiments revealed that the oxidized state of both proteins is enthalpically
stabilized. Molecular dynamics simulations suggest that changes in
the protein structure are negligible, whereas solvent reorganization
is mainly responsible for the increase in entropy during the redox
reaction. Obtained data are discussed with respect to the known structures
of the two Clds and the proposed reaction mechanism.
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Affiliation(s)
- Stefan Hofbauer
- Department of Chemistry, Division of Biochemistry, VIBT-Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, A-1190 Vienna, Austria
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31
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32
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Lee SW, Carlton C, Risch M, Surendranath Y, Chen S, Furutsuki S, Yamada A, Nocera DG, Shao-Horn Y. The Nature of Lithium Battery Materials under Oxygen Evolution Reaction Conditions. J Am Chem Soc 2012; 134:16959-62. [DOI: 10.1021/ja307814j] [Citation(s) in RCA: 250] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | | | | | | | | | - Sho Furutsuki
- Department
of Chemical System
Engineering, The University of Tokyo, 7-3-1
Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Atsuo Yamada
- Department
of Chemical System
Engineering, The University of Tokyo, 7-3-1
Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
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33
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Gemmer J, Hinrichsen Y, Abel A, Bachmann J. Systematic catalytic current enhancement for the oxidation of water at nanostructured iron(III) oxide electrodes. J Catal 2012. [DOI: 10.1016/j.jcat.2012.03.022] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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34
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Bediako DK, Lassalle-Kaiser B, Surendranath Y, Yano J, Yachandra VK, Nocera DG. Structure–Activity Correlations in a Nickel–Borate Oxygen Evolution Catalyst. J Am Chem Soc 2012; 134:6801-9. [DOI: 10.1021/ja301018q] [Citation(s) in RCA: 539] [Impact Index Per Article: 44.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- D. Kwabena Bediako
- Department of Chemistry, 6-335, Massachusetts Institute of Technology, Cambridge, Massachusetts
02139, United States
| | - Benedikt Lassalle-Kaiser
- Physical
Bioscience Division, Lawrence Berkeley National Laboratory, Berkeley, California
94720, United States
| | - Yogesh Surendranath
- Department of Chemistry, 6-335, Massachusetts Institute of Technology, Cambridge, Massachusetts
02139, United States
| | - Junko Yano
- Physical
Bioscience Division, Lawrence Berkeley National Laboratory, Berkeley, California
94720, United States
| | - Vittal K. Yachandra
- Physical
Bioscience Division, Lawrence Berkeley National Laboratory, Berkeley, California
94720, United States
| | - Daniel G. Nocera
- Department of Chemistry, 6-335, Massachusetts Institute of Technology, Cambridge, Massachusetts
02139, United States
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35
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Surendranath Y, Lutterman DA, Liu Y, Nocera DG. Nucleation, growth, and repair of a cobalt-based oxygen evolving catalyst. J Am Chem Soc 2012; 134:6326-36. [PMID: 22394103 DOI: 10.1021/ja3000084] [Citation(s) in RCA: 151] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The mechanism of nucleation, steady-state growth, and repair is investigated for an oxygen evolving catalyst prepared by electrodeposition from Co(2+) solutions in weakly basic electrolytes (Co-OEC). Potential step chronoamperometry and atomic force microscopy reveal that nucleation of Co-OEC is progressive and reaches a saturation surface coverage of ca. 70% on highly oriented pyrolytic graphite substrates. Steady-state electrodeposition of Co-OEC exhibits a Tafel slope approximately equal to 2.3 × RT/F. The electrochemical rate law exhibits a first order dependence on Co(2+) and inverse orders on proton (third order) and proton acceptor, methylphosphonate (first order for 1.8 mM ≤ [MeP(i)] ≤ 18 mM and second order dependence for 32 mM ≤ [MeP(i)] ≤ 180 mM). These electrokinetic studies, combined with recent XAS studies of catalyst structure, suggest a mechanism for steady state growth at intermediate MeP(i) concentration (1.8-18 mM) involving a rapid solution equilibrium between aquo Co(II) and Co(III) hydroxo species accompanied with a rapid surface equilibrium involving electrolyte dissociation and deprotonation of surface bound water. These equilibria are followed by a chemical rate-limiting step for incorporation of Co(III) into the growing cobaltate clusters comprising Co-OEC. At higher concentrations of MeP(i) ([MeP(i)] ≥ 32 mM), MePO(3)(2-) equilibrium binding to Co(II) in solution is suggested by the kinetic data. Consistent with the disparate pH profiles for oxygen evolution electrocatalysis and catalyst formation, NMR-based quantification of catalyst dissolution as a function of pH demonstrates functional stability and repair at pH values >6 whereas catalyst corrosion prevails at lower pH values. These kinetic insights provide a basis for developing and operating functional water oxidation (photo)anodes under benign pH conditions.
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Affiliation(s)
- Yogesh Surendranath
- Department of Chemistry, 6-335, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307, USA
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36
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Bensaid S, Centi G, Garrone E, Perathoner S, Saracco G. Towards artificial leaves for solar hydrogen and fuels from carbon dioxide. CHEMSUSCHEM 2012; 5:500-521. [PMID: 22431486 DOI: 10.1002/cssc.201100661] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The development of an "artificial leaf" that collects energy in the same way as a natural one is one of the great challenges for the use of renewable energy and a sustainable development. To avoid the problem of intermittency in solar energy, it is necessary to design systems that directly capture CO(2) and convert it into liquid solar fuels that can be easily stored. However, to be advantageous over natural leaves, it is necessary that artificial leaves have a higher solar energy-to-chemical fuel conversion efficiency, directly provide fuels that can be used in power-generating devices, and finally be robust and of easy construction, for example, smart, cheap and robust. This review discusses the recent progress in this field, with particular attention to the design and development of 'artificial leaf' devices and some of their critical components. This is a very active research area with different concepts and ideas under investigation, although often the validity of the considered solutions it is still not proven or the many constrains are not fully taken into account, particularly from the perspective of system engineering, which considerably limits some of the investigated solutions. It is also shown how system design should be included, at least at a conceptual level, in the definition of the artificial leaf elements to be investigated (catalysts, electrodes, membranes, sensitizers) and that the main relevant aspects of the cell engineering (mass/charge transport, fluid dynamics, sealing, etc.) should be also considered already at the initial stage because they determine the design and the choice between different options. For this reason, attention has been given to the system-design ideas under development instead of the molecular aspects of the O(2) - or H(2) -evolution catalysts. However, some of the recent advances in these catalysts, and their use in advanced electrodes, are also reported to provide a more complete picture of the field.
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Affiliation(s)
- Samir Bensaid
- Department of Applied Science and Technology, Politecnico di Torino, Torino, Italy
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37
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Blanc B, Mayfield JA, McDonald CA, Lukat-Rodgers GS, Rodgers KR, DuBois JL. Understanding how the distal environment directs reactivity in chlorite dismutase: spectroscopy and reactivity of Arg183 mutants. Biochemistry 2012; 51:1895-910. [PMID: 22313119 DOI: 10.1021/bi2017377] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The chlorite dismutase from Dechloromonas aromatica (DaCld) catalyzes the highly efficient decomposition of chlorite to O(2) and chloride. Spectroscopic, equilibrium thermodynamic, and kinetic measurements have indicated that Cld has two pH sensitive moieties; one is the heme, and Arg183 in the distal heme pocket has been hypothesized to be the second. This active site residue has been examined by site-directed mutagenesis to understand the roles of positive charge and hydrogen bonding in O-O bond formation. Three Cld mutants, Arg183 to Lys (R183K), Arg183 to Gln (R183Q), and Arg183 to Ala (R183A), were investigated to determine their respective contributions to the decomposition of chlorite ion, the spin state and coordination states of their ferric and ferrous forms, their cyanide and imidazole binding affinities, and their reduction potentials. UV-visible and resonance Raman spectroscopies showed that DaCld(R183A) contains five-coordinate high-spin (5cHS) heme, the DaCld(R183Q) heme is a mixture of five-coordinate and six-coordinate high spin (5c/6cHS) heme, and DaCld(R183K) contains six-coordinate low-spin (6cLS) heme. In contrast to wild-type (WT) Cld, which exhibits pK(a) values of 6.5 and 8.7, all three ferric mutants exhibited pH-independent spectroscopic signatures and kinetic behaviors. Steady state kinetic parameters of the chlorite decomposition reaction catalyzed by the mutants suggest that in WT DaCld the pK(a) of 6.5 corresponds to a change in the availability of positive charge from the guanidinium group of Arg183 to the heme site. This could be due to either direct acid-base chemistry at the Arg183 side chain or a flexible Arg183 side chain that can access various orientations. Current evidence is most consistent with a conformational adjustment of Arg183. A properly oriented Arg183 is critical for the stabilization of anions in the distal pocket and for efficient catalysis.
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Affiliation(s)
- Béatrice Blanc
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
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Zhu G, Geletii YV, Kögerler P, Schilder H, Song J, Lense S, Zhao C, Hardcastle KI, Musaev DG, Hill CL. Wateroxidation catalyzed by a new tetracobalt-substituted polyoxometalate complex: [{Co4(μ-OH)(H2O)3}(Si2W19O70)]11−. Dalton Trans 2012; 41:2084-90. [DOI: 10.1039/c1dt11211b] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Ertem MZ, Cramer CJ. Quantum chemical characterization of the mechanism of a supported cobalt-based water oxidation catalyst. Dalton Trans 2012; 41:12213-9. [DOI: 10.1039/c2dt31871g] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Yamanaka S, Kanda K, Saito T, Umena Y, Kawakami K, Shen JR, Kamiya N, Okumura M, Nakamura H, Yamaguchi K. Electronic and Spin Structures of the CaMn4O5(H2O)4 Cluster in OEC of PSII Refined to 1.9Å X-ray Resolution. ADVANCES IN QUANTUM CHEMISTRY 2012. [DOI: 10.1016/b978-0-12-396498-4.00016-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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41
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Ertem MZ, Gagliardi L, Cramer CJ. Quantum chemical characterization of the mechanism of an iron-based water oxidation catalyst. Chem Sci 2012. [DOI: 10.1039/c2sc01030e] [Citation(s) in RCA: 114] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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42
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Surendranath Y, Nocera DG. Oxygen Evolution Reaction Chemistry of Oxide-Based Electrodes. PROGRESS IN INORGANIC CHEMISTRY 2011. [DOI: 10.1002/9781118148235.ch9] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Coggins MK, Kovacs JA. Structural and spectroscopic characterization of metastable thiolate-ligated manganese(III)-alkylperoxo species. J Am Chem Soc 2011; 133:12470-3. [PMID: 21776951 DOI: 10.1021/ja205520u] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Metastable Mn-peroxo species are proposed to form as key intermediates in biological oxidation reactions involving O(2) and C-H bond activation. The majority of these have yet to be spectroscopically characterized, and their inherent instability, in most cases, precludes structural characterization. Cysteinate-ligated metal-peroxos have been shown to form as reactive intermediates in both heme and nonheme iron enzymes. Herein we report the only examples of isolable Mn(III)-alkylperoxo species, and the first two examples of structurally characterized synthetic thiolate-ligated metal-peroxos. Spectroscopic data, including electronic absorption and IR spectra, and ESI mass spectra for (16)O vs (18)O-labeled metastable Mn(III)-OOR (R = (t)Bu, Cm) are discussed, as well as preliminary reactivity.
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Affiliation(s)
- Michael K Coggins
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
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Huang Z, Luo Z, Geletii YV, Vickers JW, Yin Q, Wu D, Hou Y, Ding Y, Song J, Musaev DG, Hill CL, Lian T. Efficient Light-Driven Carbon-Free Cobalt-Based Molecular Catalyst for Water Oxidation. J Am Chem Soc 2011; 133:2068-71. [DOI: 10.1021/ja109681d] [Citation(s) in RCA: 311] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Zhuangqun Huang
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Zhen Luo
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Yurii V. Geletii
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - James W. Vickers
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Qiushi Yin
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - David Wu
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Yu Hou
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Yong Ding
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Jie Song
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Djamaladdin G. Musaev
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Craig L. Hill
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Tianquan Lian
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
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Knör G, Monkowius U. Photosensitization and photocatalysis in bioinorganic, bio-organometallic and biomimetic systems. ADVANCES IN INORGANIC CHEMISTRY 2011. [DOI: 10.1016/b978-0-12-385904-4.00005-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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47
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Onet CI, Zhang L, Clérac R, Jean-Denis JB, Feeney M, McCabe T, Schmitt W. Self-Assembly of Hybrid Organic−Inorganic Polyoxomolybdates: Solid-State Structures and Investigation of Formation and Core Rearrangements in Solution. Inorg Chem 2010; 50:604-13. [PMID: 21141887 DOI: 10.1021/ic101672t] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Camelia I. Onet
- School of Chemistry, Trinity College, The University of Dublin, Dublin 2, Ireland
| | - Lei Zhang
- School of Chemistry, Trinity College, The University of Dublin, Dublin 2, Ireland
| | - Rodolphe Clérac
- Centre de Recherche Paul Pascal (CRPP), Equipe “Matériaux Moléculaires Magnétiques”, CNRS, UPR 8641, 115 avenue du Dr. Albert Schweitzer, Pessac F-33600, France
- Université de Bordeaux, UPR 8641, Pessac F-33600, France
| | | | - Martin Feeney
- School of Chemistry, Trinity College, The University of Dublin, Dublin 2, Ireland
| | - Thomas McCabe
- School of Chemistry, Trinity College, The University of Dublin, Dublin 2, Ireland
| | - Wolfgang Schmitt
- School of Chemistry, Trinity College, The University of Dublin, Dublin 2, Ireland
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Harman WH, Harris TD, Freedman DE, Fong H, Chang A, Rinehart JD, Ozarowski A, Sougrati MT, Grandjean F, Long GJ, Long JR, Chang CJ. Slow magnetic relaxation in a family of trigonal pyramidal iron(II) pyrrolide complexes. J Am Chem Soc 2010; 132:18115-26. [PMID: 21141856 DOI: 10.1021/ja105291x] [Citation(s) in RCA: 296] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present a family of trigonal pyramidal iron(II) complexes supported by tris(pyrrolyl-α-methyl)amine ligands of the general formula [M(solv)(n)][(tpa(R))Fe] (M = Na, R = tert-butyl (1), phenyl (4); M = K, R = mesityl (2), 2,4,6-triisopropylphenyl (3), 2,6-difluorophenyl (5)) and their characterization by X-ray crystallography, Mössbauer spectroscopy, and high-field EPR spectroscopy. Expanding on the discovery of slow magnetic relaxation in the recently reported mesityl derivative 2, this homologous series of high-spin iron(II) complexes enables an initial probe of how the ligand field influences the static and dynamic magnetic behavior. Magnetization experiments reveal large, uniaxial zero-field splitting parameters of D = -48, -44, -30, -26, and -6.2 cm(-1) for 1-5, respectively, demonstrating that the strength of axial magnetic anisotropy scales with increasing ligand field strength at the iron(II) center. In the case of 2,6-difluorophenyl substituted 5, high-field EPR experiments provide an independent determination of the zero-field splitting parameter (D = -4.397(9) cm(-1)) that is in reasonable agreement with that obtained from fits to magnetization data. Ac magnetic susceptibility measurements indicate field-dependent, thermally activated spin reversal barriers in complexes 1, 2, and 4 of U(eff) = 65, 42, and 25 cm(-1), respectively, with the barrier of 1 constituting the highest relaxation barrier yet observed for a mononuclear transition metal complex. In addition, in the case of 1, the large range of temperatures in which slow relaxation is observed has enabled us to fit the entire Arrhenius curve simultaneously to three distinct relaxation processes. Finally, zero-field Mössbauer spectra collected for 1 and 4 also reveal the presence of slow magnetic relaxation, with two independent relaxation barriers in 4 corresponding to the barrier obtained from ac susceptibility data and to the 3D energy gap between the M(S) = ±2 and ±1 levels, respectively.
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Affiliation(s)
- W Hill Harman
- Department of Chemistry, University of California, Berkeley, California 94720, USA
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Groysman S, Villagrán D, Nocera DG. Pseudotetrahedral d(0), d(1), and d(2) metal-oxo cores within a tris(alkoxide) platform. Inorg Chem 2010; 49:10759-61. [PMID: 21049961 DOI: 10.1021/ic101968s] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Low-coordinate first-row metal complexes of d(0) [vanadium(V)], d(1) [chromium(V)], and d(2) [chromium(IV)] assume the unusual ligand field of a pseudotetrahedron when supported by a tripodal tBu(2)(Me)CO(-) alkoxide framework. Structural, spectroscopic, and reactivity studies, supported by density functional theory calculations, indicate that the d electrons in the chromium(V) and -(IV) oxo complexes reside in metal-oxygen antibonding orbitals, engendering disparate reactivity of the metal-oxo, depending on the number of d electrons present.
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Affiliation(s)
- Stanislav Groysman
- Department of Chemistry, 6-335, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139-4307, United States
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50
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Surendranath Y, Kanan MW, Nocera DG. Mechanistic Studies of the Oxygen Evolution Reaction by a Cobalt-Phosphate Catalyst at Neutral pH. J Am Chem Soc 2010; 132:16501-9. [DOI: 10.1021/ja106102b] [Citation(s) in RCA: 968] [Impact Index Per Article: 69.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yogesh Surendranath
- Department of Chemistry, 6-335, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307, United States
| | - Matthew W. Kanan
- Department of Chemistry, 6-335, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307, United States
| | - Daniel G. Nocera
- Department of Chemistry, 6-335, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307, United States
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