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![Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F55858.jpg&w=3840&q=50)
Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase
Published on: December 4, 2017
Electronic Structure of a Formal Iron(0) Porphyrin Complex Relevant to CO2 Reduction
Christina Römelt1, Jinshuai Song1,2, Maxime Tarrago1
1Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany.
Abstract:
Iron porphyrins can act as potent electrocatalysts for CO2 functionalization. The catalytically active species has been proposed to be a formal Fe(0) porphyrin complex, [Fe(TPP)]2- (TPP = tetraphenylporphyrin), generated by two-electron reduction of [FeII(TPP)]. Our combined spectroscopic and computational investigations reveal that the reduction is ligand-centered and that [Fe(TPP)]2- is best formulated as an intermediate-spin Fe(II) center that is antiferromagnetically coupled to a porphyrin diradical anion, yielding an overall singlet ground state. As such, [Fe(TPP)]2- contains two readily accessible electrons, setting the stage for CO2 reduction.
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