Nitrogen in Oxides (NITROX) (completed)
The NITROX research project addresses a novel field in high temperature solid-state ionics; effects of nitrogen defects in oxides. This initiative is timely in view of the need for development of technologies for cleaner energy conversion and the emerging field of nano ionics.
About the project
The principal objective of NITROX is to establish fundamental insight on the effects of nitrogen defects in oxides. Nitrogen defects in nano-dimensions - embracing grain boundaries, surfaces and electrodes - will be a major focus. Moreover, possible applications induced by the presence of nitrogen defects in oxidic materials for energy application will be explored.
The objectives will be addressed from both experimental and theoretical/modeling approaches:
- Concentration of nitrogen defects and their effects on transport properties will be investigated by means of conductivity techniques and isotope diffusion-annealing.
- Surfaces and interfaces will be investigated by
- impedance spectroscopy,
- Quadropole Isotope Mass Spectrometry, and furthermore
- Ab-initio density functional theory will be applied to study both static and dynamic properties of the model system.
- Static calculations will focus on the thermodynamics of nitrogen defects and also the effect of the nitrogen defects on both the local structure and on the electronic structure.
Establishing fundamental insight on the effects of nitrogen defects in the field of solid-state ionics in general, and to high-temperature proton and mixed proton-electron conductors. Nitrogen defects in nano-dimensions - embracing grain boundaries, surfaces and electrodes - will be a major focus.
- Determine the variation in the equilibrium concentration of nitrogen point-defects with conditions (temp, and gas activities) and, accordingly, its thermodynamics
- Determine the effects of nitrogen point-defects on transport properties of high temperature ionic and mixed ionic electronic conductors with emphasis on proton conductors
- Determine effects of nitrogen point- defects on surface and interface properties of ionic and mixed ionic electronic conductors
- Model theoretically the effects described in the previous subgoals
- Combine the analytical and modeling results in an integrated effort to understand and predict the behavior of nitrogen in oxides
The project is funded by The Research Council of Norway through the FRINAT programme.