TY  - JOUR
AU  - Baeumer, Christoph
AU  - Li, Jiang
AU  - Lu, Qiyang
AU  - Liang, Allen Yu-Lun
AU  - Jin, Lei
AU  - Martins, Henrique Perin
AU  - Duchoň, Tomáš
AU  - Glöß, Maria
AU  - Gericke, Sabrina M.
AU  - Wohlgemuth, Marcus A.
AU  - Giesen, Margret
AU  - Penn, Emily E.
AU  - Dittmann, Regina
AU  - Gunkel, Felix
AU  - Waser, R.
AU  - Bajdich, Michal
AU  - Nemšák, Slavomír
AU  - Mefford, J. Tyler
AU  - Chueh, William C.
TI  - Tuning electrochemically driven surface transformation in atomically flat LaNiO3 thin films for enhanced water electrolysis
JO  - Nature materials
VL  - 20
SN  - 1476-4660
CY  - Basingstoke
PB  - Nature Publishing Group
M1  - FZJ-2021-01373
SP  - 674–682
PY  - 2021
AB  - Structure–activity relationships built on descriptors of bulk and bulk-terminated surfaces are the basis for the rational design of electrocatalysts. However, electrochemically driven surface transformations complicate the identification of such descriptors. Here we demonstrate how the as-prepared surface composition of (001)-terminated LaNiO3 epitaxial thin films dictates the surface transformation and the electrocatalytic activity for the oxygen evolution reaction. Specifically, the Ni termination (in the as-prepared state) is considerably more active than the La termination, with overpotential differences of up to 150 mV. A combined electrochemical, spectroscopic and density-functional theory investigation suggests that this activity trend originates from a thermodynamically stable, disordered NiO2 surface layer that forms during the operation of Ni-terminated surfaces, which is kinetically inaccessible when starting with a La termination. Our work thus demonstrates the tunability of surface transformation pathways by modifying a single atomic layer at the surface and that active surface phases only develop for select as-synthesized surface terminations.
LB  - PUB:(DE-HGF)16
C6  - 33432142
UR  - <Go to ISI:>//WOS:000607023400007
DO  - DOI:10.1038/s41563-020-00877-1
UR  - https://juser.fz-juelich.de/record/891112
ER  -