Edge reactivity and water-assisted dissociation on cobalt oxide nanoislands

TY - JOUR

T1 - Edge reactivity and water-assisted dissociation on cobalt oxide nanoislands

AU - Fester, J.

AU - García-Melchor, M.

AU - Walton, A. S.

AU - Bajdich, Michal

AU - Li, Zheshen

AU - Lammich, L.

AU - Vojvodic, Aleksandra

AU - Lauritsen, J. V.

PY - 2017/1/30

Y1 - 2017/1/30

N2 - Transition metal oxides show great promise as Earth-abundant catalysts for the oxygen evolution reaction in electrochemical water splitting. However, progress in the development of highly active oxide nanostructures is hampered by a lack of knowledge of the location and nature of the active sites. Here we show, through atom-resolved scanning tunnelling microscopy, X-ray spectroscopy and computational modelling, how hydroxyls form from water dissociation at under coordinated cobalt edge sites of cobalt oxide nanoislands. Surprisingly, we find that an additional water molecule acts to promote all the elementary steps of the dissociation process and subsequent hydrogen migration, revealing the important assisting role of a water molecule in its own dissociation process on a metal oxide. Inspired by the experimental findings, we theoretically model the oxygen evolution reaction activity of cobalt oxide nanoislands and show that the nanoparticle metal edges also display favourable adsorption energetics for water oxidation under electrochemical conditions.

AB - Transition metal oxides show great promise as Earth-abundant catalysts for the oxygen evolution reaction in electrochemical water splitting. However, progress in the development of highly active oxide nanostructures is hampered by a lack of knowledge of the location and nature of the active sites. Here we show, through atom-resolved scanning tunnelling microscopy, X-ray spectroscopy and computational modelling, how hydroxyls form from water dissociation at under coordinated cobalt edge sites of cobalt oxide nanoislands. Surprisingly, we find that an additional water molecule acts to promote all the elementary steps of the dissociation process and subsequent hydrogen migration, revealing the important assisting role of a water molecule in its own dissociation process on a metal oxide. Inspired by the experimental findings, we theoretically model the oxygen evolution reaction activity of cobalt oxide nanoislands and show that the nanoparticle metal edges also display favourable adsorption energetics for water oxidation under electrochemical conditions.

KW - OXYGEN EVOLUTION CATALYSIS

KW - DIRECT VISUALIZATION

KW - OXIDATION

KW - ELECTROCATALYSTS

KW - SURFACES

KW - INTERFACE

KW - METALS

KW - GOLD

KW - PT(111)

KW - FILM

UR - http://www.scopus.com/inward/record.url?scp=85010957492&partnerID=8YFLogxK

U2 - 10.1038/ncomms14169

DO - 10.1038/ncomms14169

M3 - Journal article

C2 - 28134335

SN - 2041-1723

VL - 8

JO - Nature Communications

JF - Nature Communications

M1 - 14169

ER -