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Title: Elucidating the origins of enhanced CO 2 reduction in manganese electrocatalysts bearing pendant hydrogen-bond donors
Complexes of the general form [Mn(X)(CO) 3 bpy] (X = a variety of monodentate ligands, bpy = 2,2′-bipyridine) have been reported to act as electrocatalysts for the reduction of CO 2 to CO. In this work, a series of phenol and anisole substituted bipyridine ligands were synthesized and ligated to a manganese metal center in order to probe for an intramolecular hydrogen-bonding interaction in the transition state of CO 2 reduction. Ligands without the ability to intramolecularly hydrogen bond displayed decreased catalytic current density compared to those with the ability to hydrogen bond with CO 2 . Electrocatalysis was studied by performing voltammetric and bulk electrolysis experiments under argon or CO 2 environments. Measurements of catalytic rates using hydrogen vs. deuterium for the intramolecular H/D-bonding step show that there is an isotope effect associated with the catalysis. The data presented herein suggest a mechanism involving two subsequent equilibrium isotope effects in combination with a primary kinetic isotope effect.  more » « less
Award ID(s):
1800400
PAR ID:
10167522
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Dalton Transactions
Volume:
48
Issue:
33
ISSN:
1477-9226
Page Range / eLocation ID:
12730 to 12737
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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