In this section
@article{Ender:2026:10.1021/acscatal.6c00325,
author = {Ender, E and Wang, Y and Tseng, C and Taylor, HE and Dwyer, L and Li, K and Becker, H and Felisari, L and Haigh, SJ and Rao, R and Moore, KL and Walton, AS},
doi = {10.1021/acscatal.6c00325},
journal = {ACS Catalysis},
pages = {14196--14204},
title = {Surface Memory in Nickel HER Catalysts: Hydroxide Formation at Open-Circuit Potential},
url = {http://dx.doi.org/10.1021/acscatal.6c00325},
volume = {16},
year = {2026}
}
TY - JOUR
AB - <jats:title>Abstract</jats:title> <jats:p>Grid-coupled electrolyzers must keep up with the variable nature of renewable power, placing nickel-based alkaline HER catalysts under rapidly changing potentials. Yet the surface chemistry of nickel-based electrodes during transitions between biased operation and open-circuit potential (OCP) remains poorly resolved. Here we resolve the morphological and chemical evolution of Ni electrodes during cycling between reductive bias and OCP. We combine in situ X-ray photoelectron spectroscopy with isotopically labeled NanoSIMS, complemented by microscopy methods, to map morphological and chemical evolution under controlled cycling. We find that reductive bias generates a transient surface that undergoes rapid hydroxylation upon return to OCP; the Ni(OH)2 observed at OCP therefore reflects the preceding electrochemical history rather than serving as a direct degradation product or mechanistic intermediate. This “memory effect” links surface speciation to prior bias conditions and identifies OCP transitions as a critical regime for hydroxide growth and irreversible surface transformations. More broadly, the results underscore the need to account for non-steady-state operation when designing and benchmarking alkaline electrocatalysts for grid-coupled water electrolysis.</jats:p>
AU - Ender,E
AU - Wang,Y
AU - Tseng,C
AU - Taylor,HE
AU - Dwyer,L
AU - Li,K
AU - Becker,H
AU - Felisari,L
AU - Haigh,SJ
AU - Rao,R
AU - Moore,KL
AU - Walton,AS
DO - 10.1021/acscatal.6c00325
EP - 14204
PY - 2026///
SP - 14196
TI - Surface Memory in Nickel HER Catalysts: Hydroxide Formation at Open-Circuit Potential
T2 - ACS Catalysis
UR - http://dx.doi.org/10.1021/acscatal.6c00325
UR - https://doi.org/10.1021/acscatal.6c00325
VL - 16
ER -