Preparation and luminescent characteristics of Eu3+-activated MgxZn1−xGa2O4 nanocrystals

Nanometer-scale Eu-doped MgxZn1−xGa2O4 phosphor powders have been synthesized by sol–gel process. The crystallization behaviors were investigated as well as the excitation and photoluminescence spectra employed to study the luminescence properties of Eu3+ in Mg–Zn mixed gallate. The grain size gradually decreases from 32.5 to 8.6 nm as Mg content increases. The excitation spectrum varies with the composition and consists of a weak charge transfer band and intense f–f transitions. Under the excitation at 394 nm, the Eu-doped MgxZn1−xGa2O4 phosphors display strong red luminescence at about 612 nm belonging to 5D0 → 7F2 electric dipole transition. Both the emission intensity and life-time increase with the arising concentration of Mg.