Sol–gel preparation and photoluminescence properties of CaLa2(MoO4)4:Eu3+ phosphors

Spheroids for intense red emitting phosphors CaLa2(MoO4)4:Eu3+ (in brief CLM:Eu) have been prepared by the simple sol–gel method. The properties of the resulting phosphors are characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), photoluminescence (PL) spectra and decay curve. The excitation spectra of CLM:Eu phosphors present strong absorption at 395 nm, which match well with commercial light-emitting diode (LED) chips. Under the 395 nm excitation, intense red emission peak at 616 nm corresponding to 5D0→7F2 transition of Eu3+ is observed for 70 at% CLM:Eu phosphor as the optimal doping concentration. The luminescence property indicates that the local symmetry of Eu3+ ion in CLM crystal lattice has no inversion center. The luminescence properties suggest that CLM:Eu phosphor may be regarded as a potential red phosphor candidate for near-UV-LEDs.