DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Reversible and Selective CO 2 to HCO 2 Electrocatalysis near the Thermodynamic Potential

Journal Article · · Angewandte Chemie

Abstract Reversible catalysis is a hallmark of energy‐efficient chemical transformations, but can only be achieved if the changes in free energy of intermediate steps are minimized and the catalytic cycle is devoid of high transition‐state barriers. Using these criteria, we demonstrate reversible CO 2 /HCO 2 conversion catalyzed by [Pt(depe) 2 ] 2+ (depe=1,2‐ bis (diethylphosphino)ethane). Direct measurement of the free energies associated with each catalytic step correctly predicts a slight bias towards CO 2 reduction. We demonstrate how the experimentally measured free energy of each step directly contributes to the <50 mV overpotential. We also find that for CO 2 reduction, H 2 evolution is negligible and the Faradaic efficiency for HCO 2 production is nearly quantitative. A free‐energy analysis reveals H 2 evolution is endergonic, providing a thermodynamic basis for highly selective CO 2 reduction.

Sponsoring Organization:
USDOE
OSTI ID:
1597157
Journal Information:
Angewandte Chemie, Journal Name: Angewandte Chemie Journal Issue: 11 Vol. 132; ISSN 0044-8249
Publisher:
Wiley Blackwell (John Wiley & Sons)Copyright Statement
Country of Publication:
Germany
Language:
English

References (39)

Hydricity of transition-metal hydrides and its role in CO2 reduction journal January 2000
Reversible Electrocatalytic Production and Oxidation of Hydrogen at Low Overpotentials by a Functional Hydrogenase Mimic journal February 2012
Rapid Selective Electrocatalytic Reduction of Carbon Dioxide to Formate by an Iridium Pincer Catalyst Immobilized on Carbon Nanotube Electrodes journal June 2014
Reversible Electrocatalytic Production and Oxidation of Hydrogen at Low Overpotentials by a Functional Hydrogenase Mimic journal February 2012
Rapid Selective Electrocatalytic Reduction of Carbon Dioxide to Formate by an Iridium Pincer Catalyst Immobilized on Carbon Nanotube Electrodes journal June 2014
Single Iridium Pincer Complex for Roundtrip Electrochemical Conversion between Carbon Dioxide and Formate journal March 2019
Formate: an Energy Storage and Transport Bridge between Carbon Dioxide and a Formate Fuel Cell in a Single Device journal October 2015
Electrocatalysts for hydrogen evolution reaction journal April 2017
Direct formate fuel cells: A review journal July 2016
Renewable Formate from C–H Bond Formation with CO 2 : Using Iron Carbonyl Clusters as Electrocatalysts journal August 2017
Thermodynamic Hydricity of Transition Metal Hydrides journal June 2016
Tailoring Electrocatalysts for Selective CO 2 or H + Reduction: Iron Carbonyl Clusters as a Case Study journal November 2015
pH-Dependent Reactivity of a Water-Soluble Nickel Complex: Hydrogen Evolution vs Selective Electrochemical Hydride Generation journal October 2018
Electrochemical CO 2 Reduction to Formic Acid at Low Overpotential and with High Faradaic Efficiency on Carbon-Supported Bimetallic Pd–Pt Nanoparticles journal June 2015
Achieving Reversible H 2 /H + Interconversion at Room Temperature with Enzyme-Inspired Molecular Complexes: A Mechanistic Study journal August 2016
Hydricity of Transition-Metal Hydrides: Thermodynamic Considerations for CO 2 Reduction journal January 2018
Molecular Catalysis of Electrochemical Reactions. Cyclic Voltammetry of Systems Approaching Reversibility journal July 2018
Electroreduction of Carbon Dioxide to Formate by Homogeneous Ir Catalysts in Water journal October 2018
Thermodynamic Considerations for Optimizing Selective CO 2 Reduction by Molecular Catalysts journal March 2019
Development of Molecular Electrocatalysts for CO2 Reduction and H2 Production/Oxidation journal December 2009
Determining the Overpotential for a Molecular Electrocatalyst journal December 2013
H 2 Evolution and Molecular Electrocatalysts: Determination of Overpotentials and Effect of Homoconjugation journal November 2010
Direct Determination of Equilibrium Potentials for Hydrogen Oxidation/Production by Open Circuit Potential Measurements in Acetonitrile journal June 2012
Measurement of the Hydride Donor Abilities of [HM(diphosphine) 2 ] + Complexes (M = Ni, Pt) by Heterolytic Activation of Hydrogen journal March 2002
Selective Electrocatalytic Reduction of CO 2 to Formate by Water-Stable Iridium Dihydride Pincer Complexes journal March 2012
Understanding and Tuning the Catalytic Bias of Hydrogenase journal May 2012
Reversible Interconversion of CO 2 and Formate by a Molybdenum-Containing Formate Dehydrogenase journal October 2014
Relative Hydride, Proton, and Hydrogen Atom Transfer Abilities of [HM(diphosphine) 2 ]PF 6 Complexes (M = Pt, Ni) journal December 1999
Solvation Effects on Transition Metal Hydricity journal November 2015
Electrocatalytic Hydrogen Evolution under Acidic Aqueous Conditions and Mechanistic Studies of a Highly Stable Molecular Catalyst journal July 2016
Molecular Cobalt Complexes with Pendant Amines for Selective Electrocatalytic Reduction of Carbon Dioxide to Formic Acid journal March 2017
Understanding and Design of Bidirectional and Reversible Catalysts of Multielectron, Multistep Reactions journal June 2019
Designing electrochemically reversible H2 oxidation and production catalysts journal August 2018
The kinetics and mechanism of the organo-iridium-catalysed enantioselective reduction of imines journal January 2016
CO 2 reduction or HCO 2 oxidation? Solvent-dependent thermochemistry of a nickel hydride complex journal January 2017
Reversible interconversion of carbon dioxide and formate by an electroactive enzyme journal July 2008
Electrocatalytic mechanism of reversible hydrogen cycling by enzymes and distinctions between the major classes of hydrogenases journal July 2012
Directing the reactivity of metal hydrides for selective CO 2 reduction journal November 2018
Combining theory and experiment in electrocatalysis: Insights into materials design journal January 2017