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  • Atom-by-atom electrodeposition of single isolated cobalt oxide molecules and clusters for studying the oxygen evolution reaction
Title: Atom-by-atom electrodeposition of single isolated cobalt oxide molecules and clusters for studying the oxygen evolution reaction
We report an electrodeposition protocol for preparing isolated cobalt oxide single molecules (Co1Ox) and clusters (ConOy) on a carbon fiber nanoelectrode. The as-prepared deposits are able to produce well-defined steady-state voltammograms for the oxygen evolution reaction (OER) in alkaline media, where the equivalent radius (rd) is estimated by the limiting current of hydroxide oxidation in accordance with the electrocatalytic amplification model. The size of isolated clusters obtained from the femtomolar Co2+solution through an atom-by-atom technique can reach as small as 0.21 nm (rd) which is approximately the length of Co–O bond in cobalt oxide. Therefore, the deposit was close to that of a Co1Oxsingle molecule with only one cobalt ion, the minimum unit of the cobalt-based oxygen-evolving catalyst. Additionally, the size-dependent catalysis of the OER on ConOydeposits shows a faster relative rate on the smaller cluster in terms of the potential at a given current density, implying the single molecular catalyst shows a superior OER activity.  more » « less
Award ID(s):
1707384
PAR ID:
10156459
Author(s) / Creator(s):
;
Publisher / Repository:
Proceedings of the National Academy of Sciences
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
117
Issue:
23
ISSN:
0027-8424
Page Range / eLocation ID:
p. 12651-12656
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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