Abstract
A bifunctional, chelating N-heterocyclic carbene-pyridine (NHC-pyridine) containing Mn(I) complex [MnBr(NHC-pyridine)(CO)3] displays a strong selectivity for CO2 reduction over proton reduction. Interestingly, the two-electron reduction of this complex occurs at a single potential, as opposed to MnBr(bpy)(CO)3, which is reduced by two electrons in two separate one-electron reductions. Here, the Gibbs free energy barriers, reduction potentials, rate constants, and pKa values are predicted with theory to understand the one- vs two-electron reduction mechanism. The effects of weak and strong Brønsted acids [HCl, TFE (2,2,2-trifluoroethanol), PhOH, CH3OH, and H2O] are studied to gauge the preference for CO2 vs proton reduction; water is found to be an ideal proton donor that allows for strong CO2 selectivity.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 8821-8831 |
| Number of pages | 11 |
| Journal | Journal of Physical Chemistry C |
| Volume | 120 |
| Issue number | 16 |
| DOIs | |
| State | Published - Apr 28 2016 |
Bibliographical note
Funding Information:We thank IIT Indore for the lab and computing facilities. This work was supported by DST-SERB [Grant no. EMR/2015/002057], Government of India, New Delhi. K.S.R. thanks UGC for the research fellowship, and A.M. and I.C. thank MHRD for the research fellowships.
Publisher Copyright:
© 2016 American Chemical Society.
Copyright:
Copyright 2016 Elsevier B.V., All rights reserved.
