Research and improvement of the optical properties of persistent luminescent oxide ceramics (2020.-2022.)

Project leader Virgīnija Vītola

Agreement No 1.1.1.2/16/I/001

Research application No 1.1.1.2/VIAA/3/19/440

Long lasting luminescence (known also as persistent luminescence) is a process where a material, after some kind of excitation, emits visible light for minutes or even hours after the excitation source has been switched off. The luminescent materials are usually obtained in the form of non-transparent powders – thus limiting the emission to the surface of the material. There might be a solution to this problem – it has recently been demonstrated that the transparency of ceramics in the visible spectral region increases the intensity of the persistent luminescence emission by exciting the entire volume of the host and allowing most of the emitted light to reach the surface. High translucency of strontium aluminate phosphors would lead to increased efficiency of persistent luminescence process, thus providing even more applications. Therefore, this research project is aimed to improve the performance of persistent luminescence materials by exploring the relationship between the physical properties of ceramic materials and their processing conditions.

Project is being carried out at Institute of Solid State Physics, University of Latvia for 36 months starting from no 01.01.2020. until 31.12.2022. The total costs of the project are 133 805.88 EUR.


Project progress

07.07.2020

Cooperation with the University of Tampere and the University of Turku has been carried out, resulting in the synthesis of transparent long-lasting luminescent glass ceramics and their luminescent and structure measurements. Publication “Low temperature afterglow from SrAl2O4: Eu, Dy, B containing glass”, has been submitted and is currently under reviewed in the journal Scripta Materialia. Mobility has been started at partner institution Tartu University, the Institute of Physics, where in collaboration with Dr. Phys Tanel Kaambre the PostDoc researcher is acquiring XPS measurement and data analysis skills.

 

28.03.2020.

In the first months of project execution, work has been carried out on literature study on transparent ceramics, as well as initial attempts to produce transparent persistent luminescence ceramics. Effects of boron on luminescent properties of strontium aluminate activated by europium has been investigated and published  "The boron effect on low temperature luminescence of SrAl2O4:Eu, Dy" Vitola, V.,  Bite, I., Millers, D., Zolotarjovs, A., Laganovska, K., Smits, K., Spustaka, A., Ceramics International (2020)  Article in press (available online),  https://doi.org/10.1016/j.ceramint.2020.01.208

The first results of the project were delivered as a public lecture on University of Latvia Young Physicists School, that was attended by approximately 200 high-school students (http://jfs.lu.lv/materialas-vertibas/).