Enhanced photoluminescence of core-shell CoFe2O4/SiO2/Y2O3:Eu3+ composite by remanent magnetization

A core-shell cobalt ferrite/silicon dioxide/europium ion-doped Y2O3 (CoFe2O4/SiO2/Y2O3:Eu3+) composite was synthesized by a facile layer-by-layer method. Magnetization of the composite under an external magnetic field of approximately 0.25 T enhanced the photoluminescence (PL) intensity by 56%. The remanent magnetization of the CoFe2O4 core increased the excited charge-transfer transition between O2- and Eu3+ in the Y2O3: Eu3+ shell, thus enhancing the probability of radiative transition (D-5(0)-> F-7(2)) of Eu3+ ions and leading to enhanced PL. Remanent magnetization is a noncontact, easy-to-operate technique with high growth amplitude and potential for practical application for smart display devices.