4 research outputs found
Luminescence spectra of YAG:Се phosphors synthesized in a field of radiation
The paper presents the measurement results of the luminescence band shape for YAG phosphors upon photoexcitation. It is shown that the position and FWHM does not depend on the excitation technique, but it depends on the phosphor prehistory. The observed difference is assumed to be due to the difference in the structure of nanodefects in phosphors synthesized under different conditions
Electron Beam-Assisted Synthesis of YAG:Ce Ceramics
The work was carried out within the framework of the grant AP14870696 of the Ministry of Education and Science of the Republic of Kazakhstan. This research was funded by the Russian Science Foundation of the Russian Federation. (Grant No. 23-73-00108). A.I.P is also thankful for financial support from Latvian Project LZP-2018/1-0214. In addition, A.I.P. is thanking the Institute of Solid State Physics, University of Latvia (ISSP UL). ISSP UL as the Centre of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD01-2016-2017-Teaming Phase2 under grant agreement No. 739508, project CAMART2.In this work, we present the results of the structure and luminescence properties of YAG:Ce (Y3Al5O12 doped with Ce3+ ions) ceramic samples. Their synthesis was carried out by sintering samples from the initial oxide powders under the powerful action of a high-energy electron beam with an energy of 1.4 MeV and a power density of 22–25 kW/cm2. The measured diffraction patterns of the synthesized ceramics are in good agreement with the standard for YAG. Luminescence characteristics at stationary/time-resolved regimes were studied. It is shown that under the influence of a high-power electron beam on a mixture of powders, it is possible to synthesize YAG:Ce luminescent ceramics with characteristics close to the well-known YAG:Ce phosphor ceramics obtained by traditional methods of solid-state synthesis. Thus, it has been demonstrated that the technology of radiation synthesis of luminescent ceramics is very promising. © 2023 by the authors. --//-- Karipbayev Z.T., Lisitsyn V.M., Golkovski M.G., Zhilgildinov Z.S., Popov A.I., Zhunusbekov A.M., Polisadova E., Tulegenova A., Mussakhanov D.A., Alpyssova G., Piskunov S.; Electron Beam-Assisted Synthesis of YAG:Ce Ceramics; (2023) Materials, 16 (11), art. no. 4102; DOI: 10.3390/ma16114102; https://www.scopus.com/inward/record.uri?eid=2-s2.0-85161490971&doi=10.3390%2fma16114102&partnerID=40&md5=e33da4c2d44c563881bdeffe410d734b published under the CC BY 4.0 licence.Grant AP14870696 of the Ministry of Education and Science of the Republic of Kazakhstan; Russian Science Foundation of the Russian Federation Grant No. 23-73-00108; the Latvian Council of Science LZP-2018/1-0214; ISSP UL as the Centre of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD01-2016-2017-Teaming Phase2 under grant agreement No. 739508, project CAMART2
Luminescence Efficiency of Cerium-doped Yttrium Aluminum Garnet Ceramics Formed by Radiation Assisted Synthesis
The variety of applications of yttrium-aluminum garnet (YAG)-based luminescent materials and the morphology necessary for these purposes required the development of many technologies for their synthesis. All synthesis technologies used are complex. The structural phase of yttrium-aluminum garnet is formed with any technology, at temperatures exceeding 1,500 °C. The starting materials for the synthesis are metal oxides of aluminum, yttrium and other oxides for activation and modification. It seems possible to use hard radiation to form a new phase. Radiation synthesis of ceramics is realized in less than 1 s, without the use of any additives and influences.
The synthesis was carried out at the electron accelerator of the Institute of Nuclear Physics (Novosibirsk). In this work, we studied the spectral-kinetic and quantitative characteristics of luminescence for the first time obtained by the method of radiation synthesis of ceramic samples of yttrium-aluminum garnet doped with cerium with statistical processing of their values. The dependences of the reproducibility of the spectral characteristics of the luminescence of the samples on the preliminary preparation of the charge for synthesis have been investigated. Several cycles of luminophore brightness studies have been performed.
It is shown that the obtained ceramics based on yttrium-aluminum garnet doped with cerium possesses the required spectral-kinetic properties, and the efficiency of conversion of the chip radiation into luminescence is achieved, which is comparable to that available in commercial phosphors. The maximum measured values of the position of the bands are from 553.5 to 559.6 nm. Brightness values range from 4,720 to 1,960 cd/m2.
It was found that the main reason for the scatter in the characteristics of the luminescent properties of ceramics of yttrium-aluminum garnet, activated by cerium obtained by radiation assisted synthesis is the high rate of synthesis and, especially, the high rate of cooling of the samples