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Information × Registration Number 0224U000361, 0122U000415 , R & D reports Title New near-infrared luminescent materials based on modified tetrapyrrole and complex oxide compounds of d- and f-elements: synthesis, design, properties popup.stage_title Head Dotsenko Volodymyr P., Доктор хімічних наук Registration Date 05-01-2024 Organization Physico-Chemical Institute O. Bogatsky National Academy of Sciences of Ukraine popup.description2  Techniques for obtaining new photostable luminescent materials based on tetrapyrrole and lanthanide-tetrapyrrole compounds were developed, as well as a technique for the synthesis of 5,10,15-tris(pentafluorophenyl)corrole was developed and optimized. It is shown that the use of organic polymers (poly(methyl methacrylate)) or inorganic compounds (SiO2) as carriers in combination with different types of their binding with tetrapyrrole and lanthanide-tetrapyrrole compounds allows obtaining highly efficient luminescent systems. In particular, when using even a low concentration of lanthanide-porphyrin of 0.1% in the final material, the efficiency of infrared emission of the Yb(III) ion remains at the level of the corresponding methanol solution. It was found that the emission characteristics (for the visible and near-infrared ranges) of the obtained materials are stable within a year from the moment of their receipt. Cr3+ ion-doped orthoborates MBO3 (M= Ga, Sc, In) with calcite structure were synthesized by solid-phase reactions and investigated by X-ray diffraction, SEM and luminescent spectroscopy. It is shown that at 293 K, the luminescence spectrum of Cr3+ ions in GaBO3 contains a non-elemental band with a maximum at 710 nm and is a superposition of emissions from two excited states of Cr3+ ions - 2E and 4Т2. With an increase in the size of the coordination polyhedron (i.e., the M-O distance), the strength of the crystal field at the Cr3+ site decreases and the luminescence spectra of Cr3+ in MBO3 (M= Sc, In) consist of a broad band with a maximum at 805-810 nm, which is related to the spin-allowed transition 4T2 → 4A2. Based on the data of luminescent spectroscopy, it was concluded that, in contrast to MBO3 (M= Sc, In), the symmetry of the surrounding of Cr3+ ions in GaBO3 is lower than the point symmetry of the metal (S6). From the practical point of view, InBO3 doped with Cr3+ ions is the most promising luminescent material. Product Description popup.authors Efryushina Ninel P. Berezovska Iryna V. Halushchenko Valeriia Serhiyivna Dotsenko Volodymyr P. Korovin Oleksandr Yu. Linnyk Valeriia Valeriyivna Pochinoc Ilvera V. Rusakova Natalya V. Semenishyn Mykola M. Smola Serhii S. Khomenko Olena V. popup.nrat_date 2024-01-05 Close