Anomalous diffusion along metal/ceramic interfaces.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 30531799.
- Also identified by DOI 10.1038/s41467-018-07724-7 and PMC identifier 6286315.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Interface diffusion along a metal/ceramic interface present in numerous energy and electronic devices can critically affect their performance and stability. Hole formation in a polycrystalline Ni film on an α-Al<sub>2</sub>O<sub>3</sub> substrate coupled with a continuum diffusion analysis demonstrates that Ni diffusion along the Ni/α-Al<sub>2</sub>O<sub>3</sub> interface is surprisingly fast. Ab initio calculations demonstrate that both Ni vacancy formation and migration energies at the coherent Ni/α-Al<sub>2</sub>O<sub>3</sub> interface are much smaller than in bulk Ni, suggesting that the activation energy for diffusion along coherent Ni/α-Al<sub>2</sub>O<sub>3</sub> interfaces is comparable to that along (incoherent/high angle) grain boundaries. Based on these results, we develop a simple model for diffusion along metal/ceramic interfaces, apply it to a wide range of metal/ceramic systems and validate it with several ab initio calculations. These results suggest that fast metal diffusion along metal/ceramic interfaces should be common, but is not universal.