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Su X, Li S, Yan L. N-H Bond Activation Catalyzed by an Anderson-Type Polyoxometalate-Based Compound: Key Role of Transition-Metal Heteroatom. Inorg Chem 2023; 62:15673-15679. [PMID: 37708077 DOI: 10.1021/acs.inorgchem.3c02462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/16/2023]
Abstract
Polyoxometalates (POMs) have a broad array of applied platforms with well-characterized catalysis to achieve N-H bond activation. Herein, the mechanism of the Anderson-type POM-based catalyst [FeIIIMoVI6O18{(OCH2)3CNH2}2]3- ([TrisFeIIIMoVI6O18]3-, Tris = {(OCH2)3CNH2}2) for the N-H bond activation of hydrazine (PhHNNHPh) was investigated by density functional theory calculations. The results reveal that [TrisFeIIIMoVI6O18]3- as the active species is responsible for the continuous abstraction of two electrons and two protons of PhHNNHPh via a proton-coupled electron transfer pathway, resulting in the activation of two N-H bonds in PhHNNHPh and thus the product PhNNPh. H2O2 acts as an oxidant to regulate catalyst regeneration. Based on the proposed catalytic mechanism, the key role of the heteroatom FeIII in [TrisFeIIIMoVI6O18]3- was disclosed. The d-orbital of FeIII in [TrisFeIIIMoVI6O18]3- acts as an electron receptor to promote the electron transfer (ET) in the rate-determining step (RDS) of the catalytic cycle. The substitution of the heteroatom FeIII of [TrisFeIIIMoVI6O18]3- with CoIII, RuIII, or MnIII is expected to improve the catalytic activity for several reasons: (i) the unoccupied molecular orbitals of POM-based compounds containing CoIII or RuIII are low, which is beneficial for the ET of RDS; (ii) For N-H bond activation catalyzed by the MnIII-containing POM-based compound, the transition state of RDS is stable because the d-orbital of its active site is half-filled, which results in a low free-energy barrier.
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Affiliation(s)
- Xiaofang Su
- Collaborative Innovation Centre of Henan Province for Green Manufacturing of Fine Chemicals, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007, Henan, P. R. China
| | - Shujun Li
- Collaborative Innovation Centre of Henan Province for Green Manufacturing of Fine Chemicals, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007, Henan, P. R. China
| | - Likai Yan
- Key Laboratory of Polyoxometalate Science of Ministry of Education, Institute of Functional Material Chemistry, Faculty of Chemistry, Northeast Normal University, Changchun 130018, P. R. China
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Korenev VS, Burilova EA, Volchek VV, Benassi E, Amirov RR, Sokolov MN, Abramov PA. NMR-Relaxometric Investigation of Mn(II)-Doped Polyoxometalates in Aqueous Solutions. Int J Mol Sci 2023; 24:ijms24087308. [PMID: 37108471 PMCID: PMC10139238 DOI: 10.3390/ijms24087308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Revised: 04/08/2023] [Accepted: 04/11/2023] [Indexed: 04/29/2023] Open
Abstract
Solution behavior of K;5[(Mn(H2O))PW11O39]·7H2O (1), Na3.66(NH4)4.74H3.1[(MnII(H2O))2.75(WO(H2O))0.25(α-B-SbW9O33)2]·27H2O (2), and Na4.6H3.4[(MnII(H2O)3)2(WO2)2(β-B-TeW9O33)2]·19H2O (3) was studied with NMR-relaxometry and HPLC-ICP-AES (High Performance Liquid Chromatography coupled with Inductively Coupled Plasma Atomic Emission Spectroscopy). According to the data, the [(Mn(H2O))PW11O39]5- Keggin-type anion is the most stable in water among the tested complexes, even in the presence of ethylenediaminetetraacetic acid (EDTA) or diethylenetriaminepentaacetic acid (DTPA). Aqueous solutions of 2 and 3 anions are less stable and contain other species resulting from dissociation of Mn2+. Quantum chemical calculations show the change in Mn2+ electronic state between [Mn(H2O)6]2+ and [(Mn(H2O))PW11O39]5-.
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Affiliation(s)
- Vladimir S Korenev
- Nikolaev Institute of Inorganic Chemistry SB RAS, 3 Akad. Lavrentiev Ave., Novosibirsk 630090, Russia
| | - Evgenia A Burilova
- A.M. Butlerov Chemical Institute, Kazan Federal University, Kremlevskaya Str. 18, Kazan 420008, Russia
- A.E. Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center of RAS, Arbuzov Street 8, Kazan 420088, Russia
| | - Victoria V Volchek
- Nikolaev Institute of Inorganic Chemistry SB RAS, 3 Akad. Lavrentiev Ave., Novosibirsk 630090, Russia
| | - Enrico Benassi
- Faculty of Natural Sciences, Novosibirsk State University, 1 Pirogova Str., Novosibirsk 630090, Russia
| | - Rustem R Amirov
- A.M. Butlerov Chemical Institute, Kazan Federal University, Kremlevskaya Str. 18, Kazan 420008, Russia
| | - Maxim N Sokolov
- Nikolaev Institute of Inorganic Chemistry SB RAS, 3 Akad. Lavrentiev Ave., Novosibirsk 630090, Russia
| | - Pavel A Abramov
- Nikolaev Institute of Inorganic Chemistry SB RAS, 3 Akad. Lavrentiev Ave., Novosibirsk 630090, Russia
- Research School of Chemistry and Applied Biomedical Sciences, Tomsk Polytechnic University, Tomsk 634034, Russia
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Shi LL, Li M, You B, Liao RZ. Theoretical Study on the Electro-Reduction of Carbon Dioxide to Methanol Catalyzed by Cobalt Phthalocyanine. Inorg Chem 2022; 61:16549-16564. [PMID: 36216788 DOI: 10.1021/acs.inorgchem.2c00739] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Density functional theory (DFT) calculations have been conducted to investigate the mechanism of cobalt(II) tetraamino phthalocyanine (CoPc-NH2) catalyzed electro-reduction of CO2. Computational results show that the catalytically active species 1 (4[CoII(H4L)]0) is formed by a four-electron-four-proton reduction of the initial catalyst CoPc-NH2. Complex 1 can attack CO2 after a one-electron reduction to give a [CoIII-CO22-]- intermediate, followed by a protonation and a one-electron reduction to give intermediate [CoII-COOH]- (4). Complex 4 is then protonated on its hydroxyl group by a carbonic acid to generate the critical species 6 (CoIII-L•--CO), which can release the carbon monoxide as an intermediate (and also as a product). In parallel, complex 6 can go through a successive four-electron-four-proton reduction to produce the targeted product methanol without forming formaldehyde as an intermediate product. The high-lying π orbital and the low-lying π* orbital of the phthalocyanine endow the redox noninnocent nature of the ligand, which could be a dianion, a radical monoanion, or a radical trianion during the catalysis. The calculated results for the hydrogen evolution reaction indicate a higher energy barrier than the carbon dioxide reduction. This is consistent with the product distribution in the experiments. Additionally, the amino group on the phthalocyanine ligand was found to have a minor effect on the barriers of critical steps, and this accounts for the experimentally observed similar activity for these two catalysts, namely, CoPc-NH2 and CoPc.
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Affiliation(s)
- Le-Le Shi
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, Hubei Key Laboratory of Materials Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan430074, China
| | - Man Li
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, Hubei Key Laboratory of Materials Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan430074, China
| | - Bo You
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, Hubei Key Laboratory of Materials Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan430074, China
| | - Rong-Zhen Liao
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, Hubei Key Laboratory of Materials Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan430074, China
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Mirzanejad A, Varganov SA. The role of the intermediate triplet state in iron-catalyzed multi-state C-H activation. Phys Chem Chem Phys 2022; 24:20721-20727. [PMID: 36018581 DOI: 10.1039/d2cp02733j] [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
Efficient activation and functionalization of the C-H bond under mild conditions are of a great interest in chemical synthesis. We investigate the previously proposed spin-accelerated activation of the C(sp2)-H bond by a Fe(II)-based catalyst to clarify the role of the intermediate triplet state in the reaction mechanism. High-level electronic structure calculations on a small model of a catalytic system utilizing the coupled cluster with the single, double, and perturbative triple excitations [CCSD(T)] are used to select the density functional for the full-size model. Our analysis indicates that the previously proposed two-state quintet-singlet reaction pathway is unlikely to be efficient due to a very weak spin-orbit coupling between these two spin states. We propose a more favorable multi-state quintet-triplet-singlet reaction pathway and discuss the importance of the intermediate triplet state. This triplet state facilitates a spin-accelerated reaction mechanism by strongly coupling to both quintet and singlet states. Our calculations show that the C-H bond activation through the proposed quintet-triplet-singlet reaction pathway is more thermodynamically favorable than the single-state quintet and two-state singlet-quintet mechanisms.
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Affiliation(s)
- Amir Mirzanejad
- Department of Chemistry, University of Nevada, Reno, 1664 N. Virginia Street, Reno, NV 89557-0216, USA.
| | - Sergey A Varganov
- Department of Chemistry, University of Nevada, Reno, 1664 N. Virginia Street, Reno, NV 89557-0216, USA.
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Lewis TWR, Mastin EM, Theis ZC, Gutierrez MG, Bellert DJ. Measurement of time dependent product branching ratios indicates two-state reactivity in metal mediated chemical reactions. Phys Chem Chem Phys 2022; 24:2300-2308. [PMID: 35015007 DOI: 10.1039/d1cp05473b] [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
For several decades, the influence of Two State Reactivity (TSR) has been implicated in a host of reactions, but has lacked a stand-alone, definitive experimental kinetic signature identifying its occurrence. Here, we demonstrate that the measurement of a temporally dependent product branching ratio is indicative of spin inversion and is a kinetic signature of TSR. This is caused by products exiting different hypersurfaces with different rates and relative exothermicities. The composite measurement of product intensities with the same mass but with different multiplicities yield biexponential temporal dependences with the sampled product ratio changing in time. These measurements are made using the single photon initiated dissociative rearrangement reaction (SPIDRR) technique which identifies TSR but further determines the kinetic parameters for reaction along the original ground electronic surface in competition with spin inversion and its consequent TSR.
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Affiliation(s)
- Tucker W R Lewis
- Department of Chemistry and Biochemistry, Baylor University, Darrin Bellert, One Bear Place #97348, Waco, TX 76798, USA
| | - Evan M Mastin
- Department of Chemistry and Biochemistry, Baylor University, Darrin Bellert, One Bear Place #97348, Waco, TX 76798, USA
| | - Zachry C Theis
- Department of Chemistry and Biochemistry, Baylor University, Darrin Bellert, One Bear Place #97348, Waco, TX 76798, USA
| | - Michael G Gutierrez
- Department of Chemistry and Biochemistry, Baylor University, Darrin Bellert, One Bear Place #97348, Waco, TX 76798, USA
| | - Darrin J Bellert
- Department of Chemistry and Biochemistry, Baylor University, Darrin Bellert, One Bear Place #97348, Waco, TX 76798, USA
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Cárdenas G, Trentin I, Schwiedrzik L, Hernández-Castillo D, Lowe GA, Kund J, Kranz C, Klingler S, Stach R, Mizaikoff B, Marquetand P, Nogueira JJ, Streb C, González L. Activation by oxidation and ligand exchange in a molecular manganese vanadium oxide water oxidation catalyst. Chem Sci 2021; 12:12918-12927. [PMID: 34745522 PMCID: PMC8513927 DOI: 10.1039/d1sc03239a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 08/30/2021] [Indexed: 11/21/2022] Open
Abstract
Despite their technological importance for water splitting, the reaction mechanisms of most water oxidation catalysts (WOCs) are poorly understood. This paper combines theoretical and experimental methods to reveal mechanistic insights into the reactivity of the highly active molecular manganese vanadium oxide WOC [Mn4V4O17(OAc)3]3- in aqueous acetonitrile solutions. Using density functional theory together with electrochemistry and IR-spectroscopy, we propose a sequential three-step activation mechanism including a one-electron oxidation of the catalyst from [Mn2 3+Mn2 4+] to [Mn3+Mn3 4+], acetate-to-water ligand exchange, and a second one-electron oxidation from [Mn3+Mn3 4+] to [Mn4 4+]. Analysis of several plausible ligand exchange pathways shows that nucleophilic attack of water molecules along the Jahn-Teller axis of the Mn3+ centers leads to significantly lower activation barriers compared with attack at Mn4+ centers. Deprotonation of one water ligand by the leaving acetate group leads to the formation of the activated species [Mn4V4O17(OAc)2(H2O)(OH)]- featuring one H2O and one OH ligand. Redox potentials based on the computed intermediates are in excellent agreement with electrochemical measurements at various solvent compositions. This intricate interplay between redox chemistry and ligand exchange controls the formation of the catalytically active species. These results provide key reactivity information essential to further study bio-inspired molecular WOCs and solid-state manganese oxide catalysts.
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Affiliation(s)
- Gustavo Cárdenas
- Institute of Theoretical Chemistry, University of Vienna Währinger Str. 17 1090 Vienna Austria
- Chemistry Department, Universidad Autónoma de Madrid Calle Francisco Tomás y Valiente, 7 28049 Madrid Spain
| | - Ivan Trentin
- Institute of Inorganic Chemistry I, Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Ludwig Schwiedrzik
- Institute of Theoretical Chemistry, University of Vienna Währinger Str. 17 1090 Vienna Austria
| | | | - Grace A Lowe
- Institute of Inorganic Chemistry I, Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Julian Kund
- Institute of Analytical and Bioanalytical Chemistry, Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Christine Kranz
- Institute of Analytical and Bioanalytical Chemistry, Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Sarah Klingler
- Institute of Analytical and Bioanalytical Chemistry, Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Robert Stach
- Institute of Analytical and Bioanalytical Chemistry, Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Boris Mizaikoff
- Institute of Analytical and Bioanalytical Chemistry, Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Philipp Marquetand
- Institute of Theoretical Chemistry, University of Vienna Währinger Str. 17 1090 Vienna Austria
- IADCHEM, Institute for Advanced Research in Chemistry, Universidad Autónoma de Madrid Madrid Spain
| | - Juan J Nogueira
- Chemistry Department, Universidad Autónoma de Madrid Calle Francisco Tomás y Valiente, 7 28049 Madrid Spain
- IADCHEM, Institute for Advanced Research in Chemistry, Universidad Autónoma de Madrid Madrid Spain
| | - Carsten Streb
- Institute of Inorganic Chemistry I, Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Leticia González
- Institute of Theoretical Chemistry, University of Vienna Währinger Str. 17 1090 Vienna Austria
- Vienna Research Platform on Accelerating Reaction Discovery, University of Vienna Währinger Str. 17 1090 Vienna Austria
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Shaghaghi Z, Kouhsangini PS, Mohammad‐Rezaei R. Water oxidation activity of azo‐azomethine‐based Ni (II), Co (II), and Cu (II) complexes. Appl Organomet Chem 2021. [DOI: 10.1002/aoc.6103] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Zohreh Shaghaghi
- Coordination Chemistry Research Laboratory, Department of Chemistry, Faculty of Basic Science Azarbaijan Shahid Madani University Tabriz 5375171379 Iran
| | - Parya Sallakh Kouhsangini
- Coordination Chemistry Research Laboratory, Department of Chemistry, Faculty of Basic Science Azarbaijan Shahid Madani University Tabriz 5375171379 Iran
| | - Rahim Mohammad‐Rezaei
- Electrochemistry Research Laboratory, Department of Chemistry, Faculty of Basic Science Azarbaijan Shahid Madani University Tabriz 5375171379 Iran
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Xu Q, Xu B, Kong H, He P, Wang J, Kannan T, Ma P, Wang J, Niu J. Synthesis and Characterization of a Crown-Shaped 36-Molybdate Cluster and Application in Catalyzing Knoevenagel Condensation. Inorg Chem 2020; 59:10665-10672. [DOI: 10.1021/acs.inorgchem.0c01122] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Qiaofei Xu
- Henan Key Laboratory of Polyoxometalate Chemistry, Institute of Molecule and Crystal Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004, PR China
| | - Baijie Xu
- Henan Key Laboratory of Polyoxometalate Chemistry, Institute of Molecule and Crystal Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004, PR China
| | - Hui Kong
- Henan Key Laboratory of Polyoxometalate Chemistry, Institute of Molecule and Crystal Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004, PR China
| | - Peipei He
- Henan Key Laboratory of Polyoxometalate Chemistry, Institute of Molecule and Crystal Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004, PR China
| | - Jiawei Wang
- Henan Key Laboratory of Polyoxometalate Chemistry, Institute of Molecule and Crystal Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004, PR China
| | - Thirumurthy Kannan
- Henan Key Laboratory of Polyoxometalate Chemistry, Institute of Molecule and Crystal Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004, PR China
| | - Pengtao Ma
- Henan Key Laboratory of Polyoxometalate Chemistry, Institute of Molecule and Crystal Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004, PR China
| | - Jingping Wang
- Henan Key Laboratory of Polyoxometalate Chemistry, Institute of Molecule and Crystal Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004, PR China
| | - Jingyang Niu
- Henan Key Laboratory of Polyoxometalate Chemistry, Institute of Molecule and Crystal Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004, PR China
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Su XF, Guan W, Yan LK, Su ZM. Tricopper-polyoxometalate catalysts for water oxidation: Redox-inertness of copper center. J Catal 2020. [DOI: 10.1016/j.jcat.2019.11.025] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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The Reactivity and Stability of Polyoxometalate Water Oxidation Electrocatalysts. Molecules 2019; 25:molecules25010157. [PMID: 31906045 PMCID: PMC6983101 DOI: 10.3390/molecules25010157] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 12/20/2019] [Accepted: 12/27/2019] [Indexed: 01/08/2023] Open
Abstract
This review describes major advances in the use of functionalized molecular metal oxides (polyoxometalates, POMs) as water oxidation catalysts under electrochemical conditions. The fundamentals of POM-based water oxidation are described, together with a brief overview of general approaches to designing POM water oxidation catalysts. Next, the use of POMs for homogeneous, solution-phase water oxidation is described together with a summary of theoretical studies shedding light on the POM-WOC mechanism. This is followed by a discussion of heterogenization of POMs on electrically conductive substrates for technologically more relevant application studies. The stability of POM water oxidation catalysts is discussed, using select examples where detailed data is already available. The review finishes with an outlook on future perspectives and emerging themes in electrocatalytic polyoxometalate-based water oxidation research.
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Su XF, Yan LK, Su ZM. Theoretical Insight into the Performance of Mn II/III-Monosubstituted Heteropolytungstates as Water Oxidation Catalysts. Inorg Chem 2019; 58:15751-15757. [PMID: 31710211 DOI: 10.1021/acs.inorgchem.9b01806] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The performance of MnII/III-monosubstituted heteropolytungstates [MnIII(H2O)GeW11O39]5- ([GT-MnIII-OH2]5-, where GT = GeW11O39) and [MnII(H2O)GeW11O39]6- ([GT-MnII-OH2]6-) as water oxidation catalysts at pH 9 was explored using density functional theory calculations. The counterion effect was fully considered, in which five and six Na+ ions were included in the calculations for water oxidation catalyzed by [GT-MnIII-OH2]5- and [GT-MnII-OH2]6-, respectively. The process of water oxidation catalysis was divided into three elemental stages: (i) oxidative activation, (ii) O-O bond formation, and (iii) O2 evolution. In the oxidative activation stage, two electrons and two protons are removed from [Na5-GT-MnIII-OH2] and three electrons and two protons are removed from [Na6-GT-MnII-OH2]. Therefore, the MnIV-O• species [Na5-GT-MnIV-O•] is obtained. Two mechanisms, (i) water nucleophilic attack and (ii) oxo-oxo coupling, were demonstrated to be competitive in O-O bond formation triggered from [Na5-GT-MnIV-O•]. In the last stage, the O2 molecule could be readily evolved from the peroxo or dinuclear species and the catalyst returns to the ground state after the coordination of a water molecule(s).
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Affiliation(s)
- Xiao-Fang Su
- Faculty of Chemistry, National & Local United Engineering Lab for Power Battery, Key Laboratory of Polyoxometalate Science of Ministry of Education , Northeast Normal University , Changchun 130024 , People's Republic of China
| | - Li-Kai Yan
- Faculty of Chemistry, National & Local United Engineering Lab for Power Battery, Key Laboratory of Polyoxometalate Science of Ministry of Education , Northeast Normal University , Changchun 130024 , People's Republic of China
| | - Zhong-Min Su
- Faculty of Chemistry, National & Local United Engineering Lab for Power Battery, Key Laboratory of Polyoxometalate Science of Ministry of Education , Northeast Normal University , Changchun 130024 , People's Republic of China
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