@article{Pei2026, 
author = {Jinhui Pei and Xiaoqin Chen and Yanxiao Ning and Qiang Fu},
title = {Visualizing dynamic evolution of surface electrochemical potential on solid-state electrolyte via spatially resolved photoelectron measurements},
year = {2026},
journal = {Nano Research},
volume = {19},
number = {1},
pages = {94907863},
keywords = {electrochemical device, solid-state electrolyte, yttria-stabilized zirconia (YSZ), oxygen ion migration, in situ photoemission electron microscopy (PEEM), micro-region X-ray photoelectron spectroscopy (μ-XPS)},
url = {https://www.sciopen.com/article/10.26599/NR.2025.94907863},
doi = {10.26599/NR.2025.94907863},
abstract = {The dynamic evolution of surface electrochemical potential of the electrolyte plays a key role in the performance of solid-state electrochemical devices, while its real-time characterization remains challenging. Here, we visualize the dynamic evolution of the surface electrochemical potential on yttria-stabilized zirconia (YSZ) in a planar Au|YSZ|Au model cell, using spatially resolved photoelectron-based techniques including photoemission electron microscopy (PEEM) and micro-region X-ray photoelectron spectroscopy (μ-XPS). PEEM reveals two sequential reaction fronts in YSZ under cathodic polarization, corresponding to the evolution of the chemical potential of oxygen ions, with a faster propagation speed on the top surface and a slower one in the near-surface region. XPS measurements quantitatively reveal the time-dependent electric potential distribution across YSZ surface. COMSOL simulations confirm the presence of a stronger electric field at the top surface, particularly at the advancing reaction fronts, compared to the near-surface region. The critical role of the electric field in driving surface reactions is further supported by the enhanced reactions observed at the tips of the zigzag-shaped electrode edges. This work offers mechanistic insights into the coupling between electrochemical potential dynamics and electrolyte reactions.}
}