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Title: Solution Structures of Highly Active Molecular Ir Water-Oxidation Catalysts from Density Functional Theory Combined with High-Energy X-ray Scattering and EXAFS Spectroscopy

Journal Article · · Journal of the American Chemical Society
DOI:https://doi.org/10.1021/jacs.6b01750· OSTI ID:1387676
 [1];  [1];  [2];  [3];  [1];  [1];  [1];  [1];  [2];  [4];  [1]
  1. Yale Univ., New Haven, CT (United States)
  2. Argonne National Lab. (ANL), Argonne, IL (United States)
  3. Northwestern Univ., Evanston, IL (United States)
  4. Argonne National Lab. (ANL), Argonne, IL (United States); Northwestern Univ., Evanston, IL (United States)
+ Show Author Affiliations

The solution structures of highly active Ir water-oxidation catalysts are elucidated herein by combining density functional theory, high-energy X-ray scattering (HEXS), and extended X-ray absorption fine structure (EXAFS) spectroscopy. We find that the catalysts are Ir dimers with mono-μ-O cores and terminal anionic ligands, generated in situ through partial oxidation of a common catalyst precursor. The proposed structures are supported by 1H and 17O NMR, EPR, resonance Raman and UV–vis spectra, electrophoresis, etc. Our findings are particularly valuable to understand the mechanism of water oxidation by highly reactive Ir catalysts. Importantly, our DFT-EXAFS-HEXS methodology provides a new in situ technique for characterization of active species in catalytic systems.

Research Organization:
Energy Frontier Research Centers (EFRC) (United States). Argonne-Northwestern Solar Energy Research Center (ANSER); Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
Grant/Contract Number:
SC0001059; AC02-06CH11357
OSTI ID:
1387676
Journal Information:
Journal of the American Chemical Society, Vol. 138, Issue 17; Related Information: ANSER partners with Northwestern University (lead); Argonne National Laboratory; University of Chicago; University of Illinois, Urbana-Champaign; Yale University; ISSN 0002-7863
Publisher:
American Chemical Society (ACS)Copyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 54 works
Citation information provided by
Web of Science

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  • Diaz-Morales, Oscar; Hersbach, Thomas J. P.; Hetterscheid, Dennis G. H.
  • Journal of the American Chemical Society, Vol. 136, Issue 29 https://doi.org/10.1021/ja504460w
journal July 2014
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Cited By (14)

Post Synthetic Defect Engineering of UiO-66 Metal–Organic Framework with An Iridium(III)-HEDTA Complex and Application in Water Oxidation Catalysis journal October 2019
Iridium Water Oxidation Catalysts Based on Pyridine‐Carbene Alkyl‐Substituted Ligands journal March 2019
Pump–probe XAS investigation of the triplet state of an Ir photosensitizer with chromenopyridinone ligands journal January 2018
Synthesis and Characterization of Iridium(V) Coordination Complexes With an N,O-Donor Organic Ligand journal September 2017
Recent Advances in the Development of Molecular Catalyst‐Based Anodes for Water Oxidation toward Artificial Photosynthesis journal November 2018
Multihole water oxidation catalysis on haematite photoanodes revealed by operando spectroelectrochemistry and DFT journal October 2019
Kinetics and mechanisms of catalytic water oxidation journal January 2019
The Middle-Earth between Homogeneous and Heterogeneous Catalysis in Water Oxidation with Iridium: The Middle-Earth between Homogeneous and Heterogeneous Catalysis in Water Oxidation with Iridium journal November 2018
Stable iridium dinuclear heterogeneous catalysts supported on metal-oxide substrate for solar water oxidation journal March 2018
Evidence for tetranuclear bis-μ-oxo cubane species in molecular iridium-based water oxidation catalysts from XAS analysis journal January 2019
Synthesis and Characterization of Iridium(V) Coordination Complexes With an N,O-Donor Organic Ligand journal September 2017
The Middle-Earth between Homogeneous and Heterogeneous Catalysis in Water Oxidation with Iridium journal January 2019
Reactive oxygen species in iridium-based OER catalysts text January 2016
Iridium Water Oxidation Catalysts Based on Pyridine‐Carbene Alkyl‐Substituted Ligands text January 2019

Figures / Tables (6)

Chart 1(p. 1)figure Chart 1
Figure 1(p. 2)figure Figure 1
Figure 2(p. 2)figure Figure 2
Figure 3(p. 3)figure Figure 3
Scheme 1(p. 3)figure Scheme 1
Table-1(p. 3)table Table-1

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
catalysis (homogeneous)
catalysis (heterogeneous)
solar (photovoltaic)
solar (fuels)
photosynthesis (natural and artificial)
bio-inspired
hydrogen and fuel cells
electrodes - solar
defects
charge transport
spin dynamics
membrane
materials and chemistry by design
optics
synthesis (novel materials)
synthesis (self-assembly)
ligands
oligomers
catalysts
extended X-ray absorption fine structure
transition metals