Abstract
Dislocation-enhanced electrical conductivity is an emerging topic for ceramic oxides. In contrast to the majority of present studies which focus on large-scale crystal deformation or thin film fabrication to introduce dislocations, we use a nanoindentation “pop-in stop” method to locally generate 〈011〉 edge-type dislocations at room temperature, without crack formation, on the (100) surface of a rutile TiO2 single-crystal. Ion beam assisted deposition of microcontacts allowed for both deformed and non-deformed zones to be locally probed by impedance spectroscopy. Compared to the dislocation-free region, a local enhancement of the electrical conductivity by 50% in the dislocation-rich regions is found. The study paves the way for local “mechanical-doping” of ceramics and oxide materials, allowing for the use of dislocations to tune the local conductivity with high spatial resolution.
| Original language | English |
|---|---|
| Article number | 114543 |
| Journal | Scripta Materialia |
| Volume | 212 |
| DOIs | |
| Publication status | Published - 15 Apr 2022 |
| MoE publication type | A1 Journal article-refereed |
Funding
H. B. and G. D. acknowledge the financial support by the ERC Advanced Grant GB CORRELATE (Grant Agreement 787446 GB-CORRELATE). H. T. acknowledges Ph.D. fellowship from the International Max Planck Research School for Surface and Interface Engineering (IMPRS-SurMat). S.N. acknowledges the valuable discussion with Dr. Stefan Zaefferer and the algorithm search assistance by Mr Manuel Gathmann. Q. K M. acknowledges funding from the Deutscher Akademischer Austauschdienst (DAAD) for the Ph.D. fellowship with award number 91669061. X. F. acknowledges the support of the Athene Young Investigator Programme (TU Darmstadt).
Keywords
- Dislocations
- Electrical conductivity
- Impedance spectroscopy
- Mechanical doping
- Titanium dioxide