Li, M., Li, L., Zang, J. et al. (1 more author) (2015) Donor-doping and reduced leakage current in Nb-doped Na0.5Bi0.5TiO3. Applied Physics Letters, 106 (10). 102904. ISSN 0003-6951
Abstract
Low levels of so-called “donor-doping” in titanate-based perovskite oxides such as La for Ba, Sr, and Nb for Ti in (Ba, Sr)TiO3 can significantly reduce the resistivity of these typical (d0) dielectric materials and expand application areas to positive temperature coefficient resistors, thermoelectrics, conductive wafers as thin film substrates, and solid oxide fuel cell anode materials. Here, we show low levels of Nb-doping (≤1 at. %) on the Ti-site in the well-known lead-free piezoelectric perovskite oxide Na 0.5Bi0.5TiO3 (NBT) produces completely different behaviours whereby much higher resistivity is obtained, therefore indicating a different donor-doping (substitution) mechanism. There is a switch in conduction mechanism from oxygen-ions in undoped NBT with an activation energy (Ea) of <0.9 eV to electronic (band gap) conduction in 0.5–1 at. % Nb-doped NBT with Ea ∼ 1.5–1.8 eV. This demonstrates the necessity of further systematic doping studies to elucidate the defect chemistry of NBT which is clearly different to that of (Ba,Sr)TiO3. This defect chemistry needs to be understood if NBT-based materials are going to be manufactured on a large scale for commercial applications. This study also illustrates different donor-doping mechanisms to exist within the family of d0 titanate-based perovskites.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © Author(s) 2015. This is an author produced version of a paper subsequently published in Applied Physics Letters. Uploaded in accordance with the publisher's self-archiving policy. |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Engineering (Sheffield) > Department of Materials Science and Engineering (Sheffield) |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 24 Feb 2016 11:03 |
Last Modified: | 12 Mar 2016 15:38 |
Published Version: | http://dx.doi.org/10.1063/1.4914509 |
Status: | Published |
Publisher: | American Institute of Physics |
Refereed: | Yes |
Identification Number: | 10.1063/1.4914509 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:95563 |