TY  - JOUR
AU  - Görlin, Mikaela
AU  - Halldin Stenlid, Joakim
AU  - Koroidov, Sergey
AU  - Wang, Hsin-Yi
AU  - Börner, Mia
AU  - Shipilin, Mikhail
AU  - Kalinko, Aleksandr
AU  - Murzin, Vadim
AU  - Safonova, Olga V.
AU  - Nachtegaal, Maarten
AU  - Uheida, Abdusalam
AU  - Dutta, Joydeep
AU  - Bauer, Matthias
AU  - Nilsson, Anders
AU  - Diaz Morales, Oscar
TI  - Key activity descriptors of nickel-iron oxygen evolution electrocatalysts in the presence of alkali metal cations
JO  - Nature Communications
VL  - 11
IS  - 1
SN  - 2041-1723
CY  - [London]
PB  - Nature Publishing Group UK
M1  - PUBDB-2021-00380
SP  - 6181
PY  - 2020
AB  - Efficient oxygen evolution reaction (OER) electrocatalysts are pivotal for sustainable fuel production, where the Ni-Fe oxyhydroxide (OOH) is among the most active catalysts for alkaline OER. Electrolyte alkali metal cations have been shown to modify the activity and reaction intermediates, however, the exact mechanism is at question due to unexplained deviations from the cation size trend. Our X-ray absorption spectroelectrochemical results show that bigger cations shift the Ni2+/(3+δ)+ redox peak and OER activity to lower potentials (however, with typical discrepancies), following the order CsOH > NaOH ≈ KOH > RbOH > LiOH. Here, we find that the OER activity follows the variations in electrolyte pH rather than a specific cation, which accounts for differences both in basicity of the alkali hydroxides and other contributing anomalies. Our density functional theory-derived reactivity descriptors confirm that cations impose negligible effect on the Lewis acidity of Ni, Fe, and O lattice sites, thus strengthening the conclusions of an indirect pH effect.
LB  - PUB:(DE-HGF)16
C6  - pmid:33268768
UR  - <Go to ISI:>//WOS:000598904000001
DO  - DOI:10.1038/s41467-020-19729-2
UR  - https://bib-pubdb1.desy.de/record/454023
ER  -