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Information × Registration Number 0222U000232, 0119U002037 , R & D reports Title Influence of lanthanides coordination environment and size factors on the properties of lanthanide fluorophores and hybrid systems based on them popup.stage_title Head Dotsenko Volodymyr P., Доктор хімічних наук Registration Date 05-01-2022 Organization Physico-Chemical Institute O. Bogatsky National Academy of Sciences of Ukraine popup.description2 The object of research is the influence of surfactants, particle size and temperature on the luminescent properties of complex compounds of lanthanides with some drugs and aluminates of lanthanides with garnet structure. The aim of the work is to increase the luminescent characteristics of coordination and oxide compounds of Ln by modifying the structural and dimensional parameters of corresponding fluorophores. It is shown that in the presence of anionic surfactants, in particular sodium dodecylsulfate, the particle size of colloidal systems increases due to the formation of ternary complexes. The luminescence intensity of the studied complexes of Tb (III) and Eu (III) increases by 2 to 10 times. It is shown that this effect is related with the displacement of water molecules from the internal coordination sphere of the complex upon the coordination by the surfactants. Micro- and nanosized samples of doped with Ce3+, Eu3+ ions gadolinium and lutetium garnets Ln3Al5O12 (Ln = Gd, Lu) (GAG, LuAG) were are obtained by the coprecipitation method. The mechanism of thermal quenching of Ce3+ luminescence in GAG is determined. It is found that the quantum efficiency of luminescence for microsized GAG:Ce3+ samples is 0.60, while for nanosized GAG:Ce3+ samples this parameter is only 0.30-0.38. This effect is attributed to the quenching of luminescence caused by the interaction with surface defects, the role of which increases with decreasing particle size. It is concluded that GAG:Ce3+ is a promising phosphor for white LEDs of medium power. Product Description popup.authors Yegorova Alla V. Efryushina Ninel P. Berezovska Iryna V. Doha Pavlo G. Dotsenko Volodymyr P. Korovin Oleksandr Yu. Pochinoc Elvira V. Rusakova Nataliia V. Semenishyn Mykola M. Scrypynets Yulia V. Smola Serhii S. Khomenko Olena V. popup.nrat_date 2022-03-09 Close