Preparation and luminescence properties of monodisperse silica/aminosilane-coated Y2O3:Yb,Ho upconversion nanoparticles

Abstract

Monodisperse silica/aminosilane-coated Y 2 O 3 :Yb,Ho nanoparticles are prepared via homogenous precipitation combined with a polyvinylpyrrolidone-assisted ammoniation method. The factors that contribute to the success of the coating are examined, and the procedure is optimized. Compared with uncoated nanoparticles, coated nanoparticles exhibit an increased ratio of green to red emission intensity, which can mainly be attributed to the decreased number of surface defects induced by the surface coating.

Upconversion luminescence of cerium-stabilized high temperature phase zirconia phosphors with a high Er3+ doping concentration

“…ZrO 2 possesses a low phonon energy of about 470 cm À1 , good chemical and photochemical stability, a high melting point and so on, making it a good UC luminescence substrate. 5,11 As we all know, pure zirconia has three kinds of crystalline phase structure: monoclinic, tetragonal and cubic. The phase of zirconia changes with the preparation temperature and usage temperature, which causes the instability of the physical and chemical properties and hinders its application.…”

Preparation and luminescence properties of Y2O3:Er3+/TiO2 with high specific surface area

“…Y 2 O 3 is a good host material for luminescent agents because of its high chemical and photochemical stability, high melting point, potential for rare-earth doping and low phonon energy (430-500 cm 1 ) [1,2]. Er 3+ strongly absorbs throughout the infrared (IR)-ultraviolet (UV) range and thus is suitable for upconversion studies.…”