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The aim of this work was to study the effect of vacuum sintering conditions and cerium concentration on the optical, luminescent and thermal properties of yttrium-aluminum garnet based ceramics doped with Се3+ cations. Series of ceramic powders were synthesized and samples of luminescent ceramics having the composition Y3-хСехAl5O12 were synthesized where x was in the range 0.01 to 0.025 f.u. We show that the phase composition and grain size distribution of the ceramic powders do not depend on cerium concentration. Without sintering additives, an increase in vacuum sintering temperature from 1675 to 1800 °C leads to an increase in the optical transmittance of luminescent ceramic specimens from 5 to 55% at a 540 nm wavelength and an increase in the thermal conductivity of the samples from 8.4 to 9.5 W/(m ∙ K). It was found that an increase in cerium concentration leads to a shift of the luminescent band peak from 535 to 545 nm where as the width of the luminescent band decreases with an increase in vacuum sintering temperature from 1675 to 1725 °C.

Sol-gel method from zinc acetate in water was employed to synthesize nano-sized zinc oxide. The structural features of the ZnO obtained samples, their spectral features of luminescence and photoconductivity were studied. The influence of the treatment temperature on the luminescence and photoconductivity of nano-sized zinc oxide was studied. The type and energy position of the intrinsic defects involved in the luminescence and photoconductivity processes were determined.