1
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White NM, Waldie KM. Electrocatalytic formate and alcohol oxidation by hydride transfer at first-row transition metal complexes. Dalton Trans 2024; 53:11644-11654. [PMID: 38896286 DOI: 10.1039/d3dt04304e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
The electrocatalytic oxidation of carbon-based liquid fuels, such as formic acid and alcohols, has important applications for our renewable energy transition. Molecular electrocatalysts based on transition metal complexes provide the opportunity to explore the interplay between precise catalyst design and electrocatalytic activity. Recent advances have seen the development of first-row transition metal electrocatalysts for these transformations that operate via hydride transfer between the substrate and catalyst. In this Frontier article, we present the key contributions to this field and discuss the proposed mechanisms for each case. These studies also reveal the remaining challenges for formate and alcohol oxidation with first-row transition metal systems, for which we provide perspectives on future directions for next-generation electrocatalyst design.
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Affiliation(s)
- Navar M White
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, 123 Bevier Road, Piscataway, New Jersey 08854, USA.
| | - Kate M Waldie
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, 123 Bevier Road, Piscataway, New Jersey 08854, USA.
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2
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Wu YT, Kumbhar SV, Tsai RF, Yang YC, Zeng WQ, Wang YH, Hsu WC, Chiang YW, Yang T, Lu IC, Wang YH. Manipulating the Rate and Overpotential for Electrochemical Water Oxidation: Mechanistic Insights for Cobalt Catalysts Bearing Noninnocent Bis(benzimidazole)pyrazolide Ligands. ACS ORGANIC & INORGANIC AU 2024; 4:306-318. [PMID: 38855334 PMCID: PMC11157513 DOI: 10.1021/acsorginorgau.3c00061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 01/22/2024] [Accepted: 01/23/2024] [Indexed: 06/11/2024]
Abstract
Electrochemical water oxidation is known as the anodic reaction of water splitting. Efficient design and earth-abundant electrocatalysts are crucial to this process. Herein, we report a family of catalysts (1-3) bearing bis(benzimidazole)pyrazolide ligands (H 2 L1-H 2 L3). H 2 L3 contains electron-donating substituents and noninnocent components, resulting in catalyst 3 exhibiting unique performance. Kinetic studies show first-order kinetic dependence on [3] and [H2O] under neutral and alkaline conditions. In contrast to previously reported catalyst 1, catalyst 3 exhibits an insignificant kinetic isotope effect of 1.25 and zero-order dependence on [NaOH]. Based on various spectroscopic methods and computational findings, the L3Co2 III(μ-OH) species is proposed to be the catalyst resting state and the nucleophilic attack of water on this species is identified as the turnover-limiting step of the catalytic reaction. Computational studies provided insights into how the interplay between the electronic effect and ligand noninnocence results in catalyst 3 acting via a different reaction mechanism. The variation in the turnover-limiting step and catalytic potentials of species 1-3 leads to their catalytic rates being independent of the overpotential, as evidenced by Eyring analysis. Overall, we demonstrate how ligand design may be utilized to retain good water oxidation activity at low overpotentials.
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Affiliation(s)
- Yu-Ting Wu
- Department
of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Sharad V. Kumbhar
- Department
of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Ruei-Feng Tsai
- Department
of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Yung-Ching Yang
- Department
of Chemistry, National Chung Hsing University, Taichung 40227, Taiwan
| | - Wan-Qin Zeng
- Department
of Chemistry, National Chung Hsing University, Taichung 40227, Taiwan
| | - Yu-Han Wang
- Department
of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Wan-Chi Hsu
- Department
of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Yun-Wei Chiang
- Department
of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Tzuhsiung Yang
- Department
of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - I-Chung Lu
- Department
of Chemistry, National Chung Hsing University, Taichung 40227, Taiwan
| | - Yu-Heng Wang
- Department
of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
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3
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Cloward IN, Liu T, Rose J, Jurado T, Bonn AG, Chambers MB, Pitman CL, Ter Horst MA, Miller AJM. Catalyst self-assembly accelerates bimetallic light-driven electrocatalytic H 2 evolution in water. Nat Chem 2024; 16:709-716. [PMID: 38528106 DOI: 10.1038/s41557-024-01483-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Accepted: 02/21/2024] [Indexed: 03/27/2024]
Abstract
Hydrogen evolution is an important fuel-generating reaction that has been subject to mechanistic debate about the roles of monometallic and bimetallic pathways. The molecular iridium catalysts in this study undergo photoelectrochemical dihydrogen (H2) evolution via a bimolecular mechanism, providing an opportunity to understand the factors that promote bimetallic H-H coupling. Covalently tethered diiridium catalysts evolve H2 from neutral water faster than monometallic catalysts, even at lower overpotential. The unexpected origin of this improvement is non-covalent supramolecular self-assembly into nanoscale aggregates that efficiently harvest light and form H-H bonds. Monometallic catalysts containing long-chain alkane substituents leverage the self-assembly to evolve H2 from neutral water at low overpotential and with rates close to the expected maximum for this light-driven water splitting reaction. Design parameters for holding multiple catalytic sites in close proximity and tuning catalyst microenvironments emerge from this work.
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Affiliation(s)
- Isaac N Cloward
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Tianfei Liu
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- State Key Laboratory of Elemento-organic Chemistry, College of Chemistry, Nankai University, Tianjin, China
| | - Jamie Rose
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Tamara Jurado
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Annabell G Bonn
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Matthew B Chambers
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Catherine L Pitman
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Marc A Ter Horst
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Alexander J M Miller
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
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4
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Nishiori D, Menzel JP, Armada N, Reyes Cruz EA, Nannenga BL, Batista VS, Moore GF. Breaking a Molecular Scaling Relationship Using an Iron-Iron Fused Porphyrin Electrocatalyst for Oxygen Reduction. J Am Chem Soc 2024; 146:11622-11633. [PMID: 38639470 DOI: 10.1021/jacs.3c08586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/20/2024]
Abstract
The design of efficient electrocatalysts is limited by scaling relationships governing trade-offs between thermodynamic and kinetic performance metrics. This ″iron law″ of electrocatalysis arises from synthetic design strategies, where structural alterations to a catalyst must balance nucleophilic versus electrophilic character. Efforts to circumvent this fundamental impasse have focused on bioinspired applications of extended coordination spheres and charged sites proximal to a catalytic center. Herein, we report evidence for breaking a molecular scaling relationship involving electrocatalysis of the oxygen reduction reaction (ORR) by leveraging ligand design. We achieve this using a binuclear catalyst (a diiron porphyrin), featuring a macrocyclic ligand with extended electronic conjugation. This ligand motif delocalizes electrons across the molecular scaffold, improving the catalyst's nucleophilic and electrophilic character. As a result, our binuclear catalyst exhibits low overpotential and high catalytic turnover frequency, breaking the traditional trade-off between these two metrics.
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Affiliation(s)
- Daiki Nishiori
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287-1604, United States
- Center for Applied Structural Discovery (CASD), The Biodesign Institute, Arizona State University, Tempe, Arizona 85281, United States
| | - Jan Paul Menzel
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Nicholas Armada
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287-1604, United States
- Center for Applied Structural Discovery (CASD), The Biodesign Institute, Arizona State University, Tempe, Arizona 85281, United States
| | - Edgar A Reyes Cruz
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287-1604, United States
- Center for Applied Structural Discovery (CASD), The Biodesign Institute, Arizona State University, Tempe, Arizona 85281, United States
| | - Brent L Nannenga
- Center for Applied Structural Discovery (CASD), The Biodesign Institute, Arizona State University, Tempe, Arizona 85281, United States
- Chemical Engineering, School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287, United States
| | - Victor S Batista
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
- Energy Sciences Institute, Yale University, West Haven, Connecticut 06516, United States
| | - Gary F Moore
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287-1604, United States
- Center for Applied Structural Discovery (CASD), The Biodesign Institute, Arizona State University, Tempe, Arizona 85281, United States
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5
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Wicker SA, Hutchison P, Musicante RG, Kiker MT, Suffern NC, Graham DK, Rhodes LM, Binu AP, Jean-Francois SA, Graves AS, Brennessel WW, Eckenhoff WT. Hydrogen Production Using a Nickel Catalyst Combining Redox Activity and Pendent Base Effects. Inorg Chem 2024; 63:451-461. [PMID: 38113512 DOI: 10.1021/acs.inorgchem.3c03308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
With the mounting need for clean and renewable energy, catalysts for hydrogen production based on earth abundant elements are of great interest. Herein, we describe the synthesis, characterization, and catalytic activity of two nickel complexes based on the pyridinediimine ligand that possess basic nitrogen moieties of pyridine and imidazole that could potentially serve as pendent bases to enhance catalysis. Although these ligands have previously been reported to be complexed to some metal ions, they have not been applied to nickel. The nickel complex with the pendent pyridines was found to be the most active of the two, catalyzing proton reduction electrochemically with an overpotential of 490 mV. The appearance of a wave that preceded the Ni(I/0) redox couple in the presence of protons suggests that protonation of a dissociated pyridine was likely. Further evidence of this was provided with density functional theory calculations, and a mechanism of hydrogen production is proposed. Furthermore, in a light-driven system containing Ru(bpy)32+ and ascorbic acid, TON of 1400 were obtained.
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Affiliation(s)
- Scott A Wicker
- Department of Chemistry, Rhodes College, 2000 N. Parkway, Memphis, Tennessee 38112, United States
| | - Phillips Hutchison
- Department of Chemistry, Rhodes College, 2000 N. Parkway, Memphis, Tennessee 38112, United States
| | - Robert G Musicante
- Department of Chemistry, Rhodes College, 2000 N. Parkway, Memphis, Tennessee 38112, United States
| | - Meghan T Kiker
- Department of Chemistry, Rhodes College, 2000 N. Parkway, Memphis, Tennessee 38112, United States
| | - Nicholas C Suffern
- Department of Chemistry, Rhodes College, 2000 N. Parkway, Memphis, Tennessee 38112, United States
| | - Daniel K Graham
- Department of Chemistry, Rhodes College, 2000 N. Parkway, Memphis, Tennessee 38112, United States
| | - Liam M Rhodes
- Department of Chemistry, Rhodes College, 2000 N. Parkway, Memphis, Tennessee 38112, United States
| | - Aby P Binu
- Department of Chemistry, Rhodes College, 2000 N. Parkway, Memphis, Tennessee 38112, United States
| | - Stephan A Jean-Francois
- Department of Chemistry, Rhodes College, 2000 N. Parkway, Memphis, Tennessee 38112, United States
| | - Alex S Graves
- Department of Chemistry, Rhodes College, 2000 N. Parkway, Memphis, Tennessee 38112, United States
| | - William W Brennessel
- Department of Chemistry, University of Rochester, 120 Trustee Road, Rochester, New York 14627, United States
| | - William T Eckenhoff
- Department of Chemistry, Rhodes College, 2000 N. Parkway, Memphis, Tennessee 38112, United States
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6
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Reid AG, Moberg ME, Koellner CA, Machan CW, Thornton DA, Dickenson JC, Stober JJ, Turner DA, Tarring TJ, Brown CA, Harrison DP. Sterically attenuated electronic communication in cobalt complexes of meridional isoquinoline-derived ligands for applications in electrocatalysis. J Chem Phys 2023; 159:194306. [PMID: 37982482 DOI: 10.1063/5.0174177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 10/19/2023] [Indexed: 11/21/2023] Open
Abstract
The ability to synthetically tune the ligand frameworks of redox-active molecules is of critical importance to the economy of solar fuels because manipulating their redox properties can afford control over the operating potentials of sustained electrocatalytic or photoelectrocatalytic processes. The electronic and steric properties of 2,2':6',2″-terpyridine (Terpy) ligand frameworks can be tuned by functional group substitution on ligand backbones, and these correlate strongly to their Hammett parameters. The synthesis of a new series of tridentate meridional ligands of 2,4,6-trisubstituted pyridines that engineers the ability to finely tune the redox potentials of cobalt complexes to more positive potentials than that of their Terpy analogs is achieved by aryl-functionalizing at the four-position and by including isoquinoline at the two- and six-positions of pyridine (Aryl-DiQ). Their cobalt complex syntheses, their electronic properties, and their catalytic activity for carbon dioxide (CO2) reduction are reported and compared to their Terpy analogs. The cobalt derivatives generally experience a positive shift in their redox features relative to the Terpy-based analogs, covering a complementary potential range. Although those evaluated fail to produce any quantifiable products for the reduction of CO2 and suffer from long-term instability, these results suggest possible alternate strategies for stabilizing these compounds during catalysis. We speculate that lower equilibrium association constants to the cobalt center are intrinsic to these ligands, which originate from a steric interaction between protons on the pyridine and isoquinoline moieties. Nevertheless, the new Aryl-DiQ ligand framework has been engineered to selectively tune homoleptic cobalt complexes' redox potentials.
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Affiliation(s)
- Amelia G Reid
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904-4319, USA
| | - Megan E Moberg
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904-4319, USA
| | - Connor A Koellner
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904-4319, USA
| | - Charles W Machan
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904-4319, USA
| | - Diana A Thornton
- Virginia Tech, Department of Chemistry, Blacksburg, Virginia 24060, USA
| | - John C Dickenson
- Virginia Military Institute, Department of Chemistry, Lexington, Virginia 24450, USA
| | - Jeffry J Stober
- Virginia Military Institute, Department of Chemistry, Lexington, Virginia 24450, USA
| | - David A Turner
- Virginia Military Institute, Department of Chemistry, Lexington, Virginia 24450, USA
| | - Travis J Tarring
- Virginia Military Institute, Department of Chemistry, Lexington, Virginia 24450, USA
| | - Caleb A Brown
- Virginia Military Institute, Department of Chemistry, Lexington, Virginia 24450, USA
| | - Daniel P Harrison
- Virginia Military Institute, Department of Chemistry, Lexington, Virginia 24450, USA
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7
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Trowbridge L, Averkiev B, Sues PE. Electrocatalytic Hydrogen Evolution using a Nickel-based Calixpyrrole Complex: Controlling the Secondary Coordination Sphere on an Electrode Surface. Chemistry 2023; 29:e202301920. [PMID: 37665793 PMCID: PMC10842979 DOI: 10.1002/chem.202301920] [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: 06/16/2023] [Revised: 08/31/2023] [Accepted: 09/04/2023] [Indexed: 09/06/2023]
Abstract
Incorporating design elements from homogeneous catalysts to construct well defined active sites on electrode surfaces is a promising approach for developing next generation electrocatalysts for energy conversion reactions. Furthermore, if functionalities that control the electrode microenvironment could be integrated into these active sites it would be particularly appealing. In this context, a square planar nickel calixpyrrole complex, Ni(DPMDA) (DPMDA=2,2'-((diphenylmethylene)bis(1H-pyrrole-5,2-diyl))bis(methaneylylidene))bis(azaneylylidene))dianiline) with pendant amine groups is reported that forms a heterogeneous hydrogen evolution catalyst using anilinium tetrafluoroborate as the proton source. The supported Ni(DPMDA) catalyst was surprisingly stable and displayed fast reaction kinetics with turnover frequencies (TOF) up to 25,900 s-1 or 366,000 s-1 cm-2 . Kinetic isotope effect (KIE) studies revealed a KIE of 5.7, and this data, combined with Tafel slope analysis, suggested that a proton-coupled electron transfer (PCET) process involving the pendant amine groups was rate-limiting. While evidence of an outer-sphere reduction of the Ni(DPMDA) catalyst was observed, it is hypothesized that the control over the secondary coordination sphere provided by the pendant amines facilitated such high TOFs and enabled the PCET mechanism. The results reported herein provide insight into heterogeneous catalyst design and approaches for controlling the secondary coordination sphere on electrode surfaces.
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Affiliation(s)
- Logan Trowbridge
- Department of Chemistry, Kansas State University, 1212 Mid-Campus Drive North, Manhattan, Kansas, 66503, USA
| | - Boris Averkiev
- Department of Chemistry, Kansas State University, 1212 Mid-Campus Drive North, Manhattan, Kansas, 66503, USA
| | - Peter E Sues
- Department of Chemistry, Kansas State University, 1212 Mid-Campus Drive North, Manhattan, Kansas, 66503, USA
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8
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Kearney L, Brandon MP, Coleman A, Chippindale AM, Hartl F, Lalrempuia R, Pižl M, Pryce MT. Ligand-Structure Effects on N-Heterocyclic Carbene Rhenium Photo- and Electrocatalysts of CO 2 Reduction. Molecules 2023; 28:molecules28104149. [PMID: 37241890 DOI: 10.3390/molecules28104149] [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: 03/31/2023] [Revised: 04/20/2023] [Accepted: 05/13/2023] [Indexed: 05/28/2023] Open
Abstract
Three novel rhenium N-heterocyclic carbene complexes, [Re]-NHC-1-3 ([Re] = fac-Re(CO)3Br), were synthesized and characterized using a range of spectroscopic techniques. Photophysical, electrochemical and spectroelectrochemical studies were carried out to probe the properties of these organometallic compounds. Re-NHC-1 and Re-NHC-2 bear a phenanthrene backbone on an imidazole (NHC) ring, coordinating to Re by both the carbene C and a pyridyl group attached to one of the imidazole nitrogen atoms. Re-NHC-2 differs from Re-NHC-1 by replacing N-H with an N-benzyl group as the second substituent on imidazole. The replacement of the phenanthrene backbone in Re-NHC-2 with the larger pyrene gives Re-NHC-3. The two-electron electrochemical reductions of Re-NHC-2 and Re-NHC-3 result in the formation of the five-coordinate anions that are capable of electrocatalytic CO2 reduction. These catalysts are formed first at the initial cathodic wave R1, and then, ultimately, via the reduction of Re-Re bound dimer intermediates at the second cathodic wave R2. All three Re-NHC-1-3 complexes are active photocatalysts for the transformation of CO2 to CO, with the most photostable complex, Re-NHC-3, being the most effective for this conversion. Re-NHC-1 and Re-NHC-2 afforded modest CO turnover numbers (TONs), following irradiation at 355 nm, but were inactive at the longer irradiation wavelength of 470 nm. In contrast, Re-NHC-3, when photoexcited at 470 nm, yielded the highest TON in this study, but remained inactive at 355 nm. The luminescence spectrum of Re-NHC-3 is red-shifted compared to those of Re-NHC-1 and Re-NHC-2, and previously reported similar [Re]-NHC complexes. This observation, together with TD-DFT calculations, suggests that the nature of the lowest-energy optical excitation for Re-NHC-3 has π→π*(NHC-pyrene) and dπ(Re)→π*(pyridine) (IL/MLCT) character. The stability and superior photocatalytic performance of Re-NHC-3 are attributed to the extended conjugation of the π-electron system, leading to the beneficial modulation of the strongly electron-donating tendency of the NHC group.
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Affiliation(s)
- Lauren Kearney
- School of Chemical Sciences, Dublin City University, D09 K20V Dublin, Ireland
| | - Michael P Brandon
- School of Chemical Sciences, Dublin City University, D09 K20V Dublin, Ireland
| | - Andrew Coleman
- School of Chemical Sciences, Dublin City University, D09 K20V Dublin, Ireland
| | - Ann M Chippindale
- Department of Chemistry, University of Reading, Whiteknights, Reading RG6 6DX, UK
| | - František Hartl
- Department of Chemistry, University of Reading, Whiteknights, Reading RG6 6DX, UK
| | - Ralte Lalrempuia
- School of Chemical Sciences, Dublin City University, D09 K20V Dublin, Ireland
- Department of Chemistry, School of Physical Sciences, Mizoram University, Aizawl 796004, India
| | - Martin Pižl
- Department of Inorganic Chemistry, University of Chemistry and Technology Prague, Technická 5, 16628 Prague, Czech Republic
| | - Mary T Pryce
- School of Chemical Sciences, Dublin City University, D09 K20V Dublin, Ireland
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9
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Alvarez-Hernandez JL, Salamatian AA, Han JW, Bren KL. Potential- and Buffer-Dependent Selectivity for the Conversion of CO 2 to CO by a Cobalt Porphyrin-Peptide Electrocatalyst in Water. ACS Catal 2022; 12:14689-14697. [PMID: 36504916 PMCID: PMC9724230 DOI: 10.1021/acscatal.2c03297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 11/02/2022] [Indexed: 11/17/2022]
Abstract
A semisynthetic electrocatalyst for carbon dioxide reduction to carbon monoxide in water is reported. Cobalt microperoxidase-11 (CoMP11-Ac) is shown to reduce CO2 to CO with a turnover number of up to 32,000 and a selectivity of up to 88:5 CO:H2. Higher selectivity for CO production is favored by a less cathodic applied potential and use of a higher pK a buffer. A mechanistic hypothesis is presented in which avoiding the formation and protonation of a formal Co(I) species favors CO production. These results demonstrate how tuning reaction conditions impact reactivity toward CO2 reduction for a biocatalyst previously developed for H2 production.
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10
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Rettig ID, Xu J, Knight EA, Truong PT, Bowring MA. Variable Kinetic Isotope Effect Reveals a Multistep Pathway for Protonolysis of a Pt–Me Bond. Organometallics 2022. [DOI: 10.1021/acs.organomet.2c00504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Irving D. Rettig
- Department of Chemistry, Reed College, Portland, Oregon97202, United States
| | - Jingtong Xu
- Department of Chemistry, Reed College, Portland, Oregon97202, United States
| | | | - Phan T. Truong
- Department of Chemistry, Reed College, Portland, Oregon97202, United States
| | - Miriam A. Bowring
- Department of Chemistry, Reed College, Portland, Oregon97202, United States
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11
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Hsu WC, Zeng WQ, Lu IC, Yang T, Wang YH. Dinuclear Cobalt Complexes for Homogeneous Water Oxidation: Tuning Rate and Overpotential through the Non-Innocent Ligand. CHEMSUSCHEM 2022; 15:e202201317. [PMID: 36083105 DOI: 10.1002/cssc.202201317] [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: 07/13/2022] [Revised: 09/09/2022] [Indexed: 06/15/2023]
Abstract
In this study, dinuclear cobalt complexes (1 and 2) featuring bis(benzimidazole)pyrazolide-type ligands (H2 L and Me2 L) were prepared and evaluated as molecular electrocatalysts for water oxidation. Notably, 1 bearing a non-innocent ligand (H2 L) displayed faster catalytic turnover than 2 under alkaline conditions, and the base dependence of water oxidation and kinetic isotope effect analysis indicated that the reaction mediated by 1 proceeded by a different mechanism relative to 2. Spectroelectrochemical, cold-spray ionization mass spectrometric and computational studies found that double deprotonation of 1 under alkaline conditions cathodically shifted the catalysis-initiating potential and further altered the turnover-limiting step from nucleophilic water attack on (H2 L)CoIII 2 (superoxo) to deprotonation of (L)CoIII 2 (OH)2 . The rate-overpotential analysis and catalytic Tafel plots showed that 1 exhibited a significantly higher rate than previously reported Ru-based dinuclear electrocatalysts at similar overpotentials. These observations suggest that using non-innocent ligands is a valuable strategy for designing effective metal-based molecular water oxidation catalysts.
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Affiliation(s)
- Wan-Chi Hsu
- Department of Chemistry, National Tsing Hua University, 101, Sec 2, Kuang-Fu Rd., 30013, Hsinchu, Taiwan
| | - Wan-Qin Zeng
- Department of Chemistry, National Chung Hsing University, 145, Xingda Rd., South Dist., 402, Taichung, Taiwan
| | - I-Chung Lu
- Department of Chemistry, National Chung Hsing University, 145, Xingda Rd., South Dist., 402, Taichung, Taiwan
| | - Tzuhsiung Yang
- Department of Chemistry, National Tsing Hua University, 101, Sec 2, Kuang-Fu Rd., 30013, Hsinchu, Taiwan
| | - Yu-Heng Wang
- Department of Chemistry, National Tsing Hua University, 101, Sec 2, Kuang-Fu Rd., 30013, Hsinchu, Taiwan
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12
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Assaf EA, Gonell S, Chen CH, Miller AJM. Accessing and Photo-Accelerating Low-Overpotential Pathways for CO 2 Reduction: A Bis-Carbene Ruthenium Terpyridine Catalyst. ACS Catal 2022. [DOI: 10.1021/acscatal.2c03651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Eric A. Assaf
- University of North Carolina at Chapel Hill, Chapel Hill, North Carolina27599-3290, United States
| | - Sergio Gonell
- University of North Carolina at Chapel Hill, Chapel Hill, North Carolina27599-3290, United States
| | - Chun-Hsing Chen
- University of North Carolina at Chapel Hill, Chapel Hill, North Carolina27599-3290, United States
| | - Alexander J. M. Miller
- University of North Carolina at Chapel Hill, Chapel Hill, North Carolina27599-3290, United States
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13
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Narouz MR, De La Torre P, An L, Chang CJ. Multifunctional Charge and Hydrogen-Bond Effects of Second-Sphere Imidazolium Pendants Promote Capture and Electrochemical Reduction of CO 2 in Water Catalyzed by Iron Porphyrins. Angew Chem Int Ed Engl 2022; 61:e202207666. [PMID: 35878059 PMCID: PMC9452489 DOI: 10.1002/anie.202207666] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Indexed: 08/26/2023]
Abstract
Microenvironments tailored by multifunctional secondary coordination sphere groups can enhance catalytic performance at primary metal active sites in natural systems. Here, we capture this biological concept in synthetic systems by developing a family of iron porphyrins decorated with imidazolium (im) pendants for the electrochemical CO2 reduction reaction (CO2 RR), which promotes multiple synergistic effects to enhance CO2 RR and enables the disentangling of second-sphere contributions that stem from each type of interaction. Fe-ortho-im(H), which poises imidazolium units featuring both positive charge and hydrogen-bond capabilities proximal to the active iron center, increases CO2 binding affinity by 25-fold and CO2 RR activity by 2000-fold relative to the parent Fe tetraphenylporphyrin (Fe-TPP). Comparison with monofunctional analogs reveals that through-space charge effects have a greater impact on catalytic CO2 RR performance compared to hydrogen bonding in this context.
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Affiliation(s)
- Mina R Narouz
- Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720-1460, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720-1460, USA
| | - Patricia De La Torre
- Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720-1460, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720-1460, USA
| | - Lun An
- Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720-1460, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720-1460, USA
| | - Christopher J Chang
- Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720-1460, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720-1460, USA
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720-1460, USA
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14
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Narouz MR, De La Torre P, An L, Chang CJ. Multifunctional Charge and Hydrogen‐Bond Effects of Second‐Sphere Imidazolium Pendants Promote Capture and Electrochemical Reduction of CO2 in Water Catalyzed by Iron Porphyrins. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202207666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Mina R. Narouz
- UC Berkeley: University of California Berkeley Chemistry UNITED STATES
| | | | - Lun An
- UC Berkeley: University of California Berkeley Chemistry UNITED STATES
| | - Christopher J. Chang
- University of California Department of Chemistry 532A Latimer Hall 94720-1460 Berkeley UNITED STATES
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15
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Ma L, Liu N, Mei B, Yang K, Liu B, Deng K, Zhang Y, Feng H, Liu D, Duan J, Jiang Z, Yang H, Li Q. In Situ-Activated Indium Nanoelectrocatalysts for Highly Active and Selective CO 2 Electroreduction around the Thermodynamic Potential. ACS Catal 2022. [DOI: 10.1021/acscatal.2c01434] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lushan Ma
- MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Ning Liu
- MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Bingbao Mei
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China
| | - Kang Yang
- MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Bingxin Liu
- MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Kai Deng
- MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Ying Zhang
- MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Hao Feng
- MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Dong Liu
- MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Jingjing Duan
- MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Zheng Jiang
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China
| | - Hui Yang
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China
| | - Qiang Li
- MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
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16
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Wiedner ES, Appel AM, Raugei S, Shaw WJ, Bullock RM. Molecular Catalysts with Diphosphine Ligands Containing Pendant Amines. Chem Rev 2022; 122:12427-12474. [PMID: 35640056 DOI: 10.1021/acs.chemrev.1c01001] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Pendant amines play an invaluable role in chemical reactivity, especially for molecular catalysts based on earth-abundant metals. As inspired by [FeFe]-hydrogenases, which contain a pendant amine positioned for cooperative bifunctionality, synthetic catalysts have been developed to emulate this multifunctionality through incorporation of a pendant amine in the second coordination sphere. Cyclic diphosphine ligands containing two amines serve as the basis for a class of catalysts that have been extensively studied and used to demonstrate the impact of a pendant base. These 1,5-diaza-3,7-diphosphacyclooctanes, now often referred to as "P2N2" ligands, have profound effects on the reactivity of many catalysts. The resulting [Ni(PR2NR'2)2]2+ complexes are electrocatalysts for both the oxidation and production of H2. Achieving the optimal benefit of the pendant amine requires that it has suitable basicity and is properly positioned relative to the metal center. In addition to the catalytic efficacy demonstrated with [Ni(PR2NR'2)2]2+ complexes for the oxidation and production of H2, catalysts with diphosphine ligands containing pendant amines have also been demonstrated for several metals for many different reactions, both in solution and immobilized on surfaces. The impact of pendant amines in catalyst design continues to expand.
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17
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Loipersberger M, Derrick JS, Chang CJ, Head-Gordon M. Deciphering Distinct Overpotential-Dependent Pathways for Electrochemical CO 2 Reduction Catalyzed by an Iron-Terpyridine Complex. Inorg Chem 2022; 61:6919-6933. [PMID: 35452213 DOI: 10.1021/acs.inorgchem.2c00279] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
[Fe(tpyPY2Me)]2+ ([Fe]2+) is a homogeneous electrocatalyst for converting CO2 into CO featuring low overpotentials of <100 mV, near-unity selectivity, and high activity with turnover frequencies faster than 100 000 s-1. To identify the origins of its exceptional performance and inform future catalyst design, we report a combined computational and experimental study that establishes two distinct mechanistic pathways for electrochemical CO2 reduction catalyzed by [Fe]2+ as a function of applied overpotential. Electrochemical data shows the formation of two catalytic regimes at low (ηTOF/2 of 160 mV) and high (ηTOF/2 of 590 mV) overpotential plateaus. We propose that at low overpotentials [Fe]2+ undergoes a two-electron reduction, two-proton-transfer mechanism (electrochemical-electrochemical-chemical-chemical, EECC), where turnover occurs through the dicationic iron complex, [Fe]2+. Computational analysis supports the importance of the singlet ground-state electronic structure for CO2 binding and that the rate-limiting step is the second protonation in this low-overpotential regime. When more negative potentials are applied, an additional electron-transfer event occurs through either a stepwise or proton-coupled electron-transfer (PCET) pathway, enabling catalytic turnover from the monocationic iron complex ([Fe]+) via an electrochemical-chemical-electrochemical-chemical (ECEC) mechanism. Comparison of experimental kinetic data obtained from variable controlled potential electrolysis (CPE) experiments with direct product detection with calculated rates obtained from the energetic span model supports the PCET pathway as the most likely mechanism. Moreover, we build upon this mechanistic understanding to propose the design of an improved ligand framework that is predicted to stabilize the key transition states identified in our study and explore their electronic structures using an energy decomposition analysis. Taken together, this work highlights the value of synergistic computational/experimental approaches to decipher mechanisms of new electrocatalysts and direct the rational design of improved platforms.
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Affiliation(s)
- Matthias Loipersberger
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Jeffrey S Derrick
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Christopher J Chang
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.,Department of Molecular and Cell Biology, University of California, Berkeley, California 94720, United States
| | - Martin Head-Gordon
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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18
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Hsu WC, Wang YH. Homogeneous Water Oxidation Catalyzed by First-Row Transition Metal Complexes: Unveiling the Relationship between Turnover Frequency and Reaction Overpotential. CHEMSUSCHEM 2022; 15:e202102378. [PMID: 34881515 DOI: 10.1002/cssc.202102378] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 12/07/2021] [Indexed: 06/13/2023]
Abstract
The utilization of earth-abundant low-toxicity metal ions in the construction of highly active and efficient molecular catalysts promoting the water oxidation reaction is important for developing a sustainable artificial energy cycle. However, the kinetic and thermodynamic properties of the currently available molecular water oxidation catalysts (MWOCs) have not been comprehensively investigated. This Review summarizes the current status of MWOCs based on first-row transition metals in terms of their turnover frequency (TOF, a kinetic property) and overpotential (η, a thermodynamic property) and uses the relationship between log(TOF) and η to assess catalytic performance. Furthermore, the effects of the same ligand classes on these MWOCs are discussed in terms of TOF and η, and vice versa. The collective analysis of these relationships provides a metric for the direct comparison of catalyst systems and identifying factors crucial for catalyst design.
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Affiliation(s)
- Wan-Chi Hsu
- Department of Chemistry, National Tsing Hua University, 101, Sec 2, Kuang-Fu Rd., Hsinchu, 30013, Taiwan
| | - Yu-Heng Wang
- Department of Chemistry, National Tsing Hua University, 101, Sec 2, Kuang-Fu Rd., Hsinchu, 30013, Taiwan
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19
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Abstract
This tutorial review showcases recent (2015-2021) work describing ligand construction as it relates to the design of secondary coordination spheres (SCSs). Metalloenzymes, for example, utilize SCSs to stabilize reactive substrates, shuttle small molecules, and alter redox properties, promoting functional activity. In the realm of biomimetic chemistry, specific incorporation of SCS residues (e.g., Brønsted or Lewis acid/bases, crown ethers, redox groups etc.) has been shown to be equally critical to function. This contribution illustrates how fundamental advances in organic and inorganic chemistry have been used for the construction of such SCSs. These imaginative contributions have driven exciting findings in many transformations relevant to clean fuel generation, including small molecule (e.g., H+, N2, CO2, NOx, O2) reduction. In most cases, these reactions occur cooperatively, where both metal and ligand are requisite for substrate activation.
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Affiliation(s)
- Marcus W Drover
- Department of Chemistry and Biochemistry, The University of Windsor, 401 Sunset Avenue, Windsor, ON, N9B 3P4, Canada.
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20
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Gunasekara T, Tong Y, Speelman AL, Erickson JD, Appel AM, Hall MB, Wiedner ES. Role of High-Spin Species and Pendant Amines in Electrocatalytic Alcohol Oxidation by a Nickel Phosphine Complex. ACS Catal 2022. [DOI: 10.1021/acscatal.1c05509] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Thilina Gunasekara
- Center for Molecular Electrocatalysis, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Yicheng Tong
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Amy L. Speelman
- Center for Molecular Electrocatalysis, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Jeremy D. Erickson
- Center for Molecular Electrocatalysis, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Aaron M. Appel
- Center for Molecular Electrocatalysis, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Michael B. Hall
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Eric S. Wiedner
- Center for Molecular Electrocatalysis, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
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21
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Stratakes BM, Wells KA, Kurtz DA, Castellano FN, Miller AJM. Photochemical H 2 Evolution from Bis(diphosphine)nickel Hydrides Enables Low-Overpotential Electrocatalysis. J Am Chem Soc 2021; 143:21388-21401. [PMID: 34878278 DOI: 10.1021/jacs.1c10628] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Molecules capable of both harvesting light and forming new chemical bonds hold promise for applications in the generation of solar fuels, but such first-row transition metal photoelectrocatalysts are lacking. Here we report nickel photoelectrocatalysts for H2 evolution, leveraging visible-light-driven photochemical H2 evolution from bis(diphosphine)nickel hydride complexes. A suite of experimental and theoretical analyses, including time-resolved spectroscopy and continuous irradiation quantum yield measurements, led to a proposed mechanism of H2 evolution involving a short-lived singlet excited state that undergoes homolysis of the Ni-H bond. Thermodynamic analyses provide a basis for understanding and predicting the observed photoelectrocatalytic H2 evolution by a 3d transition metal based catalyst. Of particular note is the dramatic change in the electrochemical overpotential: in the dark, the nickel complexes require strong acids and therefore high overpotentials for electrocatalysis; but under illumination, the use of weaker acids at the same applied potential results in a more than 500 mV improvement in electrochemical overpotential. New insight into first-row transition metal hydride photochemistry thus enables photoelectrocatalytic H2 evolution without electrochemical overpotential (at the thermodynamic potential or 0 mV overpotential). This catalyst system does not require sacrificial chemical reductants or light-harvesting semiconductor materials and produces H2 at rates similar to molecular catalysts attached to silicon.
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Affiliation(s)
- Bethany M Stratakes
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Kaylee A Wells
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States
| | - Daniel A Kurtz
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Felix N Castellano
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States
| | - Alexander J M Miller
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
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22
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Gonell S, Assaf EA, Lloret-Fillol J, Miller AJM. An Iron Bis(carbene) Catalyst for Low Overpotential CO 2 Electroreduction to CO: Mechanistic Insights from Kinetic Zone Diagrams, Spectroscopy, and Theory. ACS Catal 2021. [DOI: 10.1021/acscatal.1c04414] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Sergio Gonell
- University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Avinguda Països Catalans, 16, Tarragona 43007, Spain
| | - Eric A. Assaf
- University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Julio Lloret-Fillol
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Avinguda Països Catalans, 16, Tarragona 43007, Spain
- Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, Barcelona 08010, Spain
| | - Alexander J. M. Miller
- University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
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