Atomic force microscopic (A, D) and scanning electron images (B, E) of a Ni/8-YSZ thin film model cell annealed at 1073 K (left) and 1123 K (right). Energy-dispersive X-ray maps with associated chemical information are shown in Panels C and F. Height profiles in Panels A and D deliver additional information on the local structure of the Ni thin film as a function of annealing temperature.
Solid oxide fuel cell technologies are essential for the storage of renewable energy and de-carbonisation. To push these technologies, a functional understanding of electrocatalytic materials under high-temperature conditions is imperative. Operando-based spectroscopic investigations, e.g., by near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) allow for unique insights into the chemical nature of active working electrodes, including the reactivity of different redox states and the adsorbate chemistry under dynamically changing electrochemical conditions. Thin-film model cells with spectroscopically accessible triple-phase boundary (TPB) regions for studies of interface states and local electrochemical processes deliver a fundamental understanding for the further development of renewable energy storage technologies.