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Information × Registration Number 0221U106674, 0121U111084 , R & D reports Title Crystalline phosphors' engineering for biomedical applications, energy saving lighting and contactless thermometry popup.stage_title Head Vasylechko Leonid О., Доктор хімічних наук Registration Date 17-12-2021 Organization Lviv Polytechnic National University popup.description2 Series of crystal phosphors based on solid solutions of perovskites (Y,Gd,La)AlO3, LaAlO3-SrTiO3, La2/3TiO3-CaTiO3, as well as alumina (Al1-xGax)2O3, (co)doped with Cr3+, Mn4+ and RE elements were synthesized and studied. On the example of a series of RAlO3 perovskites it is experimentally established and confirmed by theoretical calculations that the band gap systematically decreases with increasing ionic radius of RE elements. It is shown that the gradual substitution of R-cations leads to a systematic decrease in the depth of the traps caused by the crystal's host point defects. The calculations indicate the possibility of controlled modification of the traps depth owing to the engineering of the width of the band gap. The observed excitation bands of luminescence in solid solutions (1-x)CaTiO3–xLa2/3TiO3:Cr3+ and LaAlO3–SrTiO3:Cr3+ are suitable for efficient pumping by commercial LEDs, and emission of these compounds in the near IR region can be used for biomedical imaging. The origin of the electrons and holes centers was determined and the depth of electron traps and the position of the lowest energy of the triplet center Bi3+ relative to the bottom of the conduction band of Ca3Ga2Ge3O12:Bi were determined. It has been shown that Ca3Ga2Ge3O12 phosphor co-doped with Bi3+/Mn4+ can be used in white LEDs and also, due to intense afterglow, can be considered as a potential UV luminescent material for use in photodynamic therapy, photocatalysis, etc.  Product Description popup.authors Hreb Vasyl M. Zahrai Andrii I. Luchechko Andrii P. Stadnik Vitalii Ye. Turchak Svitlana L. Ubizskyi Serhii В. popup.nrat_date 2021-12-17 Close