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Title: Controlling Product Selectivity in Photochemical CO2 Reduction with the Redox Potential of the Photosensitizer

Journal Article · · ACS Catalysis

The ability to selectively reduce CO2 to a particular product or mixture of products is expected to play a key role in mitigation strategies aiming to alleviate the devastating impact of this greenhouse gas in our climate and oceans. Among those, the production of liquid solar fuels from CO2 and H2O will likely need cascade strategies involving multiple catalysts carrying out different functions. This will require that the catalysts doing the initial CO2 reduction steps deliver the right product or products to downstream catalysts. CO, H2 and formate are the most common products in CO2 reduction by molecular catalysts. Here, in this work, we demonstrate control over the selectivity of C1 products in photochemical CO2 reduction with the same catalyst, simply by changing the redox potential of the photosensitizer and/or the water concentration. Turnover numbers for CO generation with one of the photosensitizers under anhydrous conditions reached 85,000, one of the largest values reported to date. A combination of experimental results and DFT calculations show that control of the selectivity is achieved, in part, due to the interplay between regimes under kinetic or thermodynamic control. These regimes are largely dictated by the proton sources and the CO2 reduction byproducts generated.

Research Organization:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES). Chemical Sciences, Geosciences & Biosciences Division (CSGB)
Grant/Contract Number:
SC0012704; SC0021173
OSTI ID:
2506710
Report Number(s):
BNL-227507-2025-JAAM
Journal Information:
ACS Catalysis, Journal Name: ACS Catalysis Journal Issue: 24 Vol. 14; ISSN 2155-5435
Publisher:
American Chemical Society (ACS)Copyright Statement
Country of Publication:
United States
Language:
English

References (47)

A Highly Active N-Heterocyclic Carbene Manganese(I) Complex for Selective Electrocatalytic CO 2 Reduction to CO journal March 2018
Dinuclear Metal Synergistic Catalysis Boosts Photochemical CO 2 -to-CO Conversion journal November 2018
Aqueous Photoelectrochemical CO2 Reduction to CO and Methanol over a Silicon Photocathode Functionalized with a Cobalt Phthalocyanine Molecular Catalyst journal December 2022
The M06 suite of density functionals for main group thermochemistry, thermochemical kinetics, noncovalent interactions, excited states, and transition elements: two new functionals and systematic testing of four M06-class functionals and 12 other functionals journal July 2007
Stabilization of [Ru(bpy)2(CO)(η1-CO2)] and unprecedented reversible oxide transfer reactions from CO32− to [Ru(bpy)2(CO)2]2+ and from [Ru(bpy)2(CO)(η1-CO2)] to CO2 journal October 1998
Reaction mechanisms of catalytic photochemical CO2 reduction using Re(I) and Ru(II) complexes journal October 2018
Substantial improvement in the efficiency and durability of a photocatalyst for carbon dioxide reduction using a benzoimidazole derivative as an electron donor journal August 2013
Photocatalytic reduction of CO2 using metal complexes journal December 2015
Photoinduced electron-transfer systems consisting of electron-donating pyrenes or anthracenes and benzimidazolines for reductive transformation of carbonyl compounds journal July 2006
Homogeneously Catalyzed Electroreduction of Carbon Dioxide—Methods, Mechanisms, and Catalysts journal January 2018
Proton-Coupled Group Transfer Enables Concerted Protonation Pathways Relevant to Small-Molecule Activation journal July 2021
Low-Energy and Long-Lived Emission from Polypyridyl Ruthenium(II) Complexes Having A Stable-Radical Substituent journal March 2017
An Iron Pyridyl-Carbene Electrocatalyst for Low Overpotential CO 2 Reduction to CO journal December 2020
An Iron Bis(carbene) Catalyst for Low Overpotential CO2 Electroreduction to CO: Mechanistic Insights from Kinetic Zone Diagrams, Spectroscopy, and Theory journal December 2021
Thermodynamic Aspects of Electrocatalytic CO 2 Reduction in Acetonitrile and with an Ionic Liquid as Solvent or Electrolyte journal October 2015
Molecular Catalysts Boost the Rate of Electrolytic CO 2 Reduction journal April 2020
CO2 Conversion to Butene via a Tandem Photovoltaic–Electrochemical/Photothermocatalytic Process: A Co-design Approach to Coupled Microenvironments journal August 2024
Molecular Catalysis of Electrochemical Reactions. Mechanistic Aspects journal July 2008
Quantum Mechanical Continuum Solvation Models journal August 2005
Revised Basis Sets for the LANL Effective Core Potentials journal June 2008
Formation of a metal-hydride bond and the insertion of carbon dioxide. Key steps in the electrocatalytic reduction of carbon dioxide to formate anion journal January 1991
Ground- and excited-state properties of a photostable hemicage ruthenium(II) polypyridine complex journal November 1989
Photoreduction of CO2 Using [Ru(bpy)2(CO)L]n+ Catalysts in Biphasic Solution/Supercritical CO2 Systems journal September 2013
Ligand Structure, Conformational Dynamics, and Excited-State Electron Delocalization for Control of Photoinduced Electron Transfer Rates in Synthetic Donor-Bridge-Acceptor Systems journal April 2008
Properties of Bases in Acetonitrile as Solvent. IV. Proton Acceptor Power and Homoconjugation of Mono- and Diamines journal November 1965
Thermodynamic and Kinetic Hydricity of Ruthenium(II) Hydride Complexes journal September 2012
Elucidation of the Selectivity of Proton-Dependent Electrocatalytic CO 2 Reduction by fac -Re(bpy)(CO) 3 Cl journal October 2013
Visible-Light Photoredox Catalysis: Selective Reduction of Carbon Dioxide to Carbon Monoxide by a Nickel N -Heterocyclic Carbene–Isoquinoline Complex journal September 2013
Kinetics of the Trans Effect in Ruthenium Complexes Provide Insight into the Factors That Control Activity and Stability in CO 2 Electroreduction journal April 2020
Reduction of CO to Methanol with Recyclable Organic Hydrides journal March 2024
The Trans Effect in Electrocatalytic CO 2 Reduction: Mechanistic Studies of Asymmetric Ruthenium Pyridyl-Carbene Catalysts journal April 2019
Unexpected Roles of Triethanolamine in the Photochemical Reduction of CO 2 to Formate by Ruthenium Complexes journal December 2019
Aqueous Solvation Free Energies of Ions and Ion−Water Clusters Based on an Accurate Value for the Absolute Aqueous Solvation Free Energy of the Proton journal August 2006
Universal Solvation Model Based on Solute Electron Density and on a Continuum Model of the Solvent Defined by the Bulk Dielectric Constant and Atomic Surface Tensions
  • Marenich, Aleksandr V.; Cramer, Christopher J.; Truhlar, Donald G.
  • The Journal of Physical Chemistry B, Vol. 113, Issue 18, p. 6378-6396 https://doi.org/10.1021/jp810292n
journal May 2009
Electrochemical CO2 reduction catalyzed by ruthenium complexes [Ru(bpy)2(CO)2]2+ and [Ru(bpy)2(CO)Cl]+. Effect of pH on the formation of CO and HCOO- journal January 1987
Hydrogen Generation from Weak Acids: Electrochemical and Computational Studies in the [(η 5 -C 5 H 5 )Fe(CO) 2 ] 2 System journal September 2008
An overview of N-heterocyclic carbenes journal June 2014
An industrial perspective on catalysts for low-temperature CO2 electrolysis journal January 2021
The solvation environment of molecularly dispersed cobalt phthalocyanine determines methanol selectivity during electrocatalytic CO2 reduction journal July 2024
Catalysis of the electrochemical reduction of carbon dioxide journal January 2013
Molecular catalysis of CO 2 reduction: recent advances and perspectives in electrochemical and light-driven processes with selected Fe, Ni and Co aza macrocyclic and polypyridine complexes journal January 2020
Design principles of tandem cascade photoelectrochemical devices journal January 2021
Electrocatalytic reduction of CO2 to CO by polypyridyl ruthenium complexes journal January 2011
Photochemical reduction of carbon dioxide to carbon monoxide in water using a nickel(II) tetra-azamacrocycle complex as catalyst journal January 1987
Ab initio effective core potentials for molecular calculations. Potentials for K to Au including the outermost core orbitals journal January 1985
Splitting CO2 into CO and O2 by a single catalyst journal June 2012
What would it take for renewably powered electrosynthesis to displace petrochemical processes? journal April 2019