Project coordinator: Dr. Hab. Phys. Uldis Rogulis

Leading participant: Dr. Phys. Andris Antuzevics

Total cost: 300 000 EUR

Duration (years): 2018-2021

LZP FLPP No. LZP-2018/1-0335

The aim of this project is to develop and characterize nanostructured rare earth doped oxyfluoride glass ceramic materials tailored for highly efficient luminescence performance. In order to achieve the desired luminous properties such as high colour rendering index and quantum yield values of the emission as well as the repeatability required for practical applications it is planned employ structure sensitive X-ray diffraction and electron microscopy characterization techniques. State of art optical and magnetic resonance spectroscopy investigations at cryogenic temperatures are planned to determine the correlation of optical properties with activator local structure. The scientific novelty of this project is the emphasis on quantitative characterization of the studied materials which will advance the applicability of transparent glass ceramics for industrial use. The obtained results will be published in at least 3 articles in international journals with SNIP>1, one patent application and will serve as a foundation for future applied science project calls, including the EU Horizon program. The scope of this project contributes to Latvia’s priority direction in science “Technologies, materials and systems engineering for increased added value products and processes, and cybersecurity” and will advance the knowledge base in the smart specialization area of “Smart materials, technology and engineering systems” increasing the competitiveness of Latvian scientists in the world.

Project implementation (time period 01.04.2020. – 31.08.2021.)

Research results have been presented in 4 international conferences and in the 2 scientific publications, 1 popular scientific publication and 1 Latvian patent application, as well as in a public seminar. The main scientific achievements:

  • Chromium ion incorporation has been characterized using magnetic resonance (EPR, ENDOR) and X-ray (XPS, XANES) spectroscopy methods.

Antuzevics, A., Krieke, G., Ozols, H., Fedotovs, A., Sarakovskis, A., & Kuzmin, A. (2021). Oxidation State and Local Structure of Chromium Ions in LaOCl. Materials, 14(13), 3539. SCOPUS (SNIP – 1.261), Open Access

  • Demonstration of applicability of EPR method for characterization of Er3+ ions in glasses and glass-ceramics.

Antuzevics, A. (2020). EPR characterization of erbium in glasses and glass ceramics. Low Temperature Physics, 46(12), 1149-1153. SCOPUS, WoSc (SNIP – 0.658)

  • Photoluminescence quantum yield measurements in activated oxyfluoride glass-ceramics were performed. Measurements with europium ion activated glass and glass-ceramic samples show a quantum yield above 50%.

Project impact:

Benefit to society. The scientific community will be able to use the project’s: knowledge base created for the synthesis of new materials; developed methodology for the characterization of nanocomposite materials. Students are actively involved in scientific work, promoting their personal growth and Latvia's scientific capacity in general.

What problems could the project solve in the future? To increase the luminescence efficiency of oxyfluoride glass-ceramic materials by applying the results of optical and magnetic resonance research methods.

What's new in this project? The focus of the project is on quantitative characterization of a new perspective material class – oxyfluoride glass-ceramics – to evaluate the efficiency and repeatability of luminescence characteristics of the developed materials.

Project implementation (time period 03.09.2018. – 31.03.2020.)

Research results have been presented in 2 international conferences and in the form of 4 scientific publications, as well as in a public seminar. The main scientific achievements:

  • A literature survey of oxyfluoride glass ceramics investigations, where electron paramagnetic resonance spectroscopy technique is employed.

Antuzevics, A. (2019). EPR in glass ceramics. In Experimental Methods in the Physical Sciences (Vol. 50, pp. 161-190). Academic Press.

  • A novel method for a quantitative rare earth activator distribution assessment in glass ceramic nanocomposite materials.

Antuzevics, A., Krieke, G., Pavlovska, E., & Rogulis, U. (2019). Eu3+ ion distribution in oxyfluoride glass nanocomposites. Journal of Non-Crystalline Solids, 522, 119548.

  • Synthesis of glass ceramics containing hexagonal NaErF4 crystalline phase for the first time.

Krieke, G., Antuzevics, A., Springis, M., & Rogulis, U. (2019). Upconversion luminescence in transparent oxyfluoride glass ceramics containing hexagonal NaErF4. Journal of Alloys and Compounds, 798, 326-332.

  • Proposed mechanism of low temperature afterglow in BaY2F8 crystal.

Antuzevics, A., Fedotovs, A., Berzins, D., Rogulis, U., Auzins, K., Zolotarjovs, A., & Baldochi, S. L. (2020). Recombination luminescence of X-ray induced paramagnetic defects in BaY2F8. Journal of Luminescence, 117216.