Novel Gd2Mo4O15: Eu3+ red-emitting phosphor for UV, NUV and blue LED applications

Novel Eu 3+ activated Gd 2 Mo 4 O 15 phosphors were synthesized at the comparatively low temperature of 700   °C via solid-state reaction. X-ray powder diffraction results demonstrate that the phosphors crystallize in the triclinic crystal structure, the space group P I ¯ . The photoluminescence spectra and ultraviolet-visible (UV–vis) reflectance and transmittance spectra indicate that Eu 3+ doped Gd 2 Mo 4 O 15 phosphors show a broad and strong absorption band covering ultraviolet (UV) and near ultraviolet (NUV) regions and the crystals emit red light with peak maximum at about 618   nm under excitation of UV, NUV or blue light. The optimal doping concentration of Eu 3+ ions in Gd 2 Mo 4 O 15 phosphors is around 50   mol% and the main concentration quenching mechanism is determined to be the exchange interaction.