About the project
Ceramic oxides with high ionic and mixed ionic-electronic conductivity and chemical stability at elevated temperatures are important functional components in future green energy production and novel chemical technologies. As performance in these systems is controlled by surface exchange and bulk diffusion large efforts are devoted to developing thin nano-structured components. While bulk transport is currently well understood, the knowledge on surface exchange mechanisms, their corresponding kinetics and the relation between surface and bulk is quite poor. The project aims to develop novel approaches to design property-driven materials with nanofunctionalized surfaces and nano-structured thin films as well as necessary experimental techniques to determine catalytic properties and rate determining steps in specific processes relevant for fuel cells, electrolysers and gas separation membranes. Firstly, samples where surface and bulk kinetics may be decoupled will be fabricated. By coating catalytically active nano-particles or nano-structured layers, the surface is catalysed and the overall process may be shifted to diffusion-control. Thereby, traditional experimental techniques, including ECR, transient TG and ToF-SIMS, can be applied to determine surface exchange and diffusion coefficients uniquely and reliably. Secondly, direct surface exchange measurement techniques will be used when surface exchange dominates. Transient TG and oxygen Isotope Exchange determined by Gas Phase Analysis (IE-GPA) as well as with Pulse Isotope Exchange (PIE) will be used. Surface exchange mechanisms will be derived from atmospheric dependencies of the measured exchange rates. Inputs from numerical simulation of space charge layer models will be combined to give a full description of the potentials and defect chemistry at the gas/solid interfaces.
Financing
The project is funded by M-era.Net and financed by Norwegian research council , project number 258875
