Co-doping effect of Ca2+ on luminescent properties of BaAl2O4: Eu3+ phosphors

A series of Eu3+ and Ca2+ doped/co-doped BaAl2O4 phosphors were synthesized via a proteic sol-gel route. The effects of the co-dopant Ca2+ on the luminescent properties of BaAl2O4:Eu3+ phosphors were systematically investigated. The samples were excited with monochromatic X-rays from synchrotron radiation. The XEOL (X-ray excited optical luminescence) spectra of all samples, with or without Ca2+ co-doping, exhibit characteristic Eu2+ or Eu3+ emissions, which has significant difference concerning on intensity for rich Ca2+ samples. The total output light of the XEOL spectra increases as the energy of the X-rays photon increases at around the Eu LIII-edge absorption.