Search Menu
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information
Search Scholarly Publications

Title: X-ray Absorption Spectroscopy and Theoretical Investigation of the Reductive Protonation of Cyclopentadienyl Cobalt Compounds

Journal Article · · Inorganic Chemistry
ORCiD logo [1];  [2]; ORCiD logo [1]; ORCiD logo [3]
  1. Stanford Univ., CA (United States). Dept. of Chemistry
  2. Stanford Univ., CA (United States). Dept. of Chemistry; SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Synchrotron Radiation Lightsource (SSRL)
  3. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Synchrotron Radiation Lightsource (SSRL)
+ Show Author Affiliations

Cobalt(III) hydrides, formed via protonation of basic cobalt(I) centers, have long been recognized as key intermediates in the electrocatalytic reduction of protons to hydrogen. An understanding of the structural and electronic factors that govern their formation is key to developing more efficient and potent catalysts. A combination of Co K-edge X-ray absorption spectroscopy, extended X-ray absorption fine structure, density functional theory (DFT), and time-dependent DFT methods have been used to investigate several cyclopentadienyl (Cp) Co(III)L (L = ligand) species and their two-electron reduced Co(I) analogues. The results reveal that when L is strongly π-accepting, the reduced species demonstrates strong backbonding between the electron-rich Co(I) center and the ligand L, resulting in a weakly basic Co center that does not protonate to form a Co(III)–H. In contrast, a weakly π-accepting or σ-donating ligand system results in an electron-rich Co(I) center, which is readily protonated to form a Co(III)–H. Here, this study reveals the strength of a combined X-ray spectroscopy/theory method in understanding the role of ligands in tuning the electronic structure and subsequent reactivity of the metal center.

Research Organization:
SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Biological and Environmental Research (BER); National Science Foundation (NSF); National Institutes of Health (NIH)
Grant/Contract Number:
AC02-76SF00515; CHE-1565947
OSTI ID:
1503552
Journal Information:
Inorganic Chemistry, Vol. 58, Issue 2; ISSN 0020-1669
Publisher:
American Chemical Society (ACS)Copyright Statement
Country of Publication:
United States
Language:
English

References (55)

Proton-Coupled Electron Transfer journal November 2007
Solar Energy Supply and Storage for the Legacy and Nonlegacy Worlds journal November 2010
Proton-Coupled Electron Transfer in Molecular Electrocatalysis: Theoretical Methods and Design Principles journal April 2014
Proton-Coupled Electron Transfer journal April 2012
Toward the rational benchmarking of homogeneous H 2 -evolving catalysts journal January 2014
Proton Electroreduction Catalyzed by Cobaloximes:  Functional Models for Hydrogenases journal June 2005
A Synthetic Nickel Electrocatalyst with a Turnover Frequency Above 100,000 s-1 for H2 Production journal August 2011
Hydrogen Evolution Catalyzed by Cobaloximes journal December 2009
Proton-coupled electron transfer kinetics for the hydrogen evolution reaction of hangman porphyrins journal January 2012
Role of pendant proton relays and proton-coupled electron transfer on the hydrogen evolution reaction by nickel hangman porphyrins journal October 2014
Turning it off! Disfavouring hydrogen evolution to enhance selectivity for CO production during homogeneous CO 2 reduction by cobalt–terpyridine complexes journal January 2015
Earth-abundant hydrogen evolution electrocatalysts journal January 2014
Splitting Water with Cobalt journal July 2011
Reaction Pathways of Hydrogen-Evolving Electrocatalysts: Electrochemical and Spectroscopic Studies of Proton-Coupled Electron Transfer Processes journal May 2016
Potential-Dependent Electrocatalytic Pathways: Controlling Reactivity with p K a for Mechanistic Investigation of a Nickel-Based Hydrogen Evolution Catalyst journal October 2015
Reaction Parameters Influencing Cobalt Hydride Formation Kinetics: Implications for Benchmarking H 2 -Evolution Catalysts journal December 2016
Electrochemical Detection of Transient Cobalt Hydride Intermediates of Electrocatalytic Hydrogen Production journal June 2016
Hydrogen Generation by Hangman Metalloporphyrins journal June 2011
Breaking the Correlation between Energy Costs and Kinetic Barriers in Hydrogen Evolution via a Cobalt Pyridine-Diimine-Dioxime Catalyst journal August 2016
Multielectron Transfer at Cobalt: Influence of the Phenylazopyridine Ligand journal March 2017
Cyclopentadienyl Cobalt Complexes as Precatalysts for Electrocatalytic Hydrogen Evolution journal May 2017
Electrochemical reduction of protonated cyclopentadienylcobalt phosphine complexes journal July 1986
Electrocatalytic Dihydrogen Production with a Robust Mesoionic Pyridylcarbene Cobalt Catalyst journal September 2015
Asymmetric Synthesis of Axially Chiral 1-Aryl-5,6,7,8-tetrahydroquinolines by Cobalt-Catalyzed [2 + 2 + 2] Cycloaddition Reaction of 1-Aryl-1,7-octadiynes and Nitriles journal May 2010
New protic salts of aprotic polar solvents journal April 2004
Protonation of a Cobalt Phenylazopyridine Complex at the Ligand Yields a Proton, Hydride, and Hydrogen Atom Transfer Reagent journal September 2018
A Systematic K-edge X-ray Absorption Spectroscopic Study of Cu(III) Sites journal June 2000
X-ray absorption near-edge spectroscopy in bioinorganic chemistry: Application to M–O2 systems journal January 2013
XAS and DFT Investigation of Mononuclear Cobalt(III) Peroxo Complexes: Electronic Control of the Geometric Structure in CoO 2 versus NiO 2 Systems journal January 2011
Synthesis, Structural, and Spectroscopic Characterization and Reactivities of Mononuclear Cobalt(III)−Peroxo Complexes journal November 2010
A Multiplet Analysis of Fe K-Edge 1s → 3d Pre-Edge Features of Iron Complexes journal July 1997
Observations and interpretation of x-ray absorption edges in iron compounds and proteins journal May 1976
X-ray Absorption Pre-Edge Studies of High-spin Iron(II) Complexes journal March 1995
Observation of an electric quadrupole transition in the X-ray absorption spectrum of a Cu(II) complex journal May 1982
Polarized x-ray absorption edge spectroscopy of single-crystal copper(II) complexes journal October 1985
X-ray Absorption Edge Spectroscopy and Computational Studies on LCuO 2 Species:  Superoxide−Cu II versus Peroxide−Cu III Bonding journal June 2006
Prediction of Iron K-Edge Absorption Spectra Using Time-Dependent Density Functional Theory † journal December 2008
Prediction of high-valent iron K-edge absorption spectra by time-dependent Density Functional Theory journal January 2011
Manganese K-Edge X-Ray Absorption Spectroscopy as a Probe of the Metal–Ligand Interactions in Coordination Compounds journal December 2011
X-ray Absorption Spectroscopy Reveals an Organometallic Ni–C Bond in the CO-Treated Form of Acetyl-CoA Synthase journal February 2017
On the Non‐Orthogonality Problem Connected with the Use of Atomic Wave Functions in the Theory of Molecules and Crystals journal March 1950
Charge, bond order and valence in the AB initio SCF theory journal May 1983
Organometallic Chemistry of the Transition Metals. XI. Some New Cyclopentadienyl Derivatives of Cobalt and Rhodium journal January 1966
Synthesis and electrochemistry of Co(III) and Co(I) complexes having C5Me5 auxiliary journal June 2007
Synthesis, Structure, and Reactivity of [C 5 Me 5 CoLL‘] Complexes with L = Pyridine and L‘ = Olefin or L−L‘ = Bipyridine journal April 2000
Proton NMR Spectra of Cyclopentadiene, 1,3‐Cyclohexadiene, 1,3‐Cyclooctadiene, and 1,2‐Dihydronaphthalene journal September 1970
A short history of SHELX journal December 2007
Theoretical x-ray absorption fine structure standards journal July 1991
Ab initio curved-wave x-ray-absorption fine structure journal September 1991
Multiple-scattering calculations of x-ray-absorption spectra journal July 1995
Generalized gradient approximation for the exchange-correlation hole of a many-electron system journal December 1996
Fully optimized contracted Gaussian basis sets for atoms Li to Kr journal August 1992
Fully optimized contracted Gaussian basis sets of triple zeta valence quality for atoms Li to Kr journal April 1994
Balanced basis sets of split valence, triple zeta valence and quadruple zeta valence quality for H to Rn: Design and assessment of accuracy journal January 2005
Calculation of Solvent Shifts on Electronic g -Tensors with the Conductor-Like Screening Model (COSMO) and Its Self-Consistent Generalization to Real Solvents (Direct COSMO-RS) journal February 2006

Linked Research (2)

Similar Records

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
36 MATERIALS SCIENCE