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Information × Registration Number 0225U000012, (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 Дослідження впливу структурних особливостей модифікованих тетрапіролів та їх комплексів на фотофізичні параметри сполук, встановлення факторів, які визначають люмінесцентні характеристики; аналіз перспектив практичного використання отриманих матеріалів. Head Dotsenko Volodymyr P., Доктор хімічних наук Registration Date 02-01-2025 Organization Physico-Chemical Institute O. Bogatsky National Academy of Sciences of Ukraine popup.description1 The purpose of the study is to clarify patterns of influence of structural factors on the optical properties of systems based on modified tetrapyrroles, their complexes with ions of d- and f-elements and orthoborates of elements of Group III - potential near infrared (IR) luminescent emitters. popup.description2  With aim to obtain new luminescent near-infrared (IR) materials an ytterbium complex based on tetraphenylporphyrin modified with ethylenediaminetetraacetic acid in the ortho-position of the phenyl cycle was synthesized for the first time. The 4f-luminescence intensity of the ortho-isomer is higher compared to the para-isomer, which can be attributed to both a shortening of the donor-acceptor distance and the absence of significant acceleration of intersystem degradation, which is typical for "core"-coordinated compounds. Homo- and heteronuclear complexes of Nd(III), Yb(III), Lu(III), and Cu(II), Zn(II), Pd(II) with porphyrins were also obtained. The selective formation of compounds was achieved due to different complexation conditions of porphyrins with f- and d-metal ions. These compounds exhibit three types of simultaneous emission: fluorescence, phosphorescence, and 4f-luminescence. Promising materials have been proposed for applications in optoelectronics and medical needs. The use of organic polymers (polymethyl methacrylate) or inorganic compounds (SiO2) as carriers, combined with different types of binding, enables the creation of highly efficient luminescent materials with emission characteristics that remain stable for at least a year. The influence of temperature on the luminescent properties of Cr3+ ions in MBO3 orthoborates, potential IR emitters, has been studied. It is shown that the temperature quenching of the luminescence of Cr3+ ions in MBO3 (M= Sc, In) starts at ~330 K, while in the case of LuBO3 it is at relatively low temperatures (~220 K). Due to the favorable spectral composition of luminescence, its high quantum efficiency (QE= 0.70), Cr3+-doped InBO3 is a promising phosphor for the development of medium-power IR LEDs. Product Description popup.authors Yefriushyna Ninel P. Berezovska Iryna V. Halushchenko Valeriia S. Dotsenko Volodymyr P. Korovin Oleksandr Yu. Pochinok Ilvera V. Rusakova Natalia V. Semenishyn Mykola M. Smola Serhii S. Khomenko Olena V. popup.nrat_date 2025-01-02 Close