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Information × Registration Number 0224U032085, 0124U003283 , R & D reports Title Laser Ceramics for Detector of Harmful Substances popup.stage_title Head Ragulia Andrii V., д.т.н. Registration Date 24-07-2024 Organization Frantsevich Institute for Problems of Materials Science National Academy of Science of Ukraine popup.description2  As a result of the work carried out, a technique for the synthesis of nanopowder based on an ordered phase with a perovskite-type structure doped with Yb3+ ions was developed. According to the data of IR spectroscopy, the formation of peaks with frequencies  ~ 468 and 501 cm-1 was established, which indicate the crystallization process of the ordered structure of the LaLuO3:Yb3+ perovskite type. The resulting nanopowder is characterized by a particle size of 41 to 60 nm. As a result of the sintering of the obtained nanopowder, by the SPS method, a dense, practically non-porous ceramic material is formed. It was established that when using the SPS method, sintering of nanopowders should be carried out at temperatures below 1500 C in order to prevent polymorphic transformation of the ordered perovskite-type structure. Using the EPR spectroscopy method, it was established that Yb3+ has the electronic configuration of the outer shell 4f13, that is, a hole in the f-shell corresponding to the electron spin of this ion S=1/2. Its EPR spectrum occurs below about 75 K. The spectrum is broad but has clear peaks associated with three g-factors and three components of the electron-nuclear hyperfine (HF) interaction. It was established that upon excitation in the region of interband transitions, the emission intensity in the sintered LaLuO3:Yb ceramic sample and LaLuO3:4%Yb, LaLuO3:1%Yb nanopowders are consistent. However, at low-energy excitation (about 3.5 eV in the powders and about 4.1-4.3 eV, 3.6 eV in the sintered sample), the emission intensity of the powders is much higher compared to the sintered ceramic sample. Product Description popup.authors Zamula Maryna V. Korniienko Oksana A. Rahulia Andrii V. Tomila Tamara V. Shyrokov Oleksandr V. Yurchenko Yurii V. popup.nrat_date 2024-07-24 Close