Luminescence properties of YAl3(BO3)4:Gd3+ phosphors substituted with Sc3+ ions

YAl3(BO3)4:Gd3+ is an ultraviolet phosphor giving 3.97-eV emission line under the excitation by vacuum ultraviolet light. On the basis of a theoretical material design using first-principles molecular orbital calculations, Sc3+ ions were proposed as a promising dopant to improve the luminescent properties of the YAl3(BO3)4:Gd3+ phosphor. In this work, YAl3(BO3)4:Gd3+ phosphors substituted with Sc3+ ions were synthesized and their luminescence and excitation spectra were measured at room temperature. The observed excitation spectra of Y(Al,Sc)3(BO3)4 :Gd3+ and (Y,Sc)Al3(BO3)4 :Gd3+ phosphors actually show the additional absorption structure on the lower-energy side of the fundamental absorption edge of YAl3(BO3)4:Gd3+ phosphors and the associated luminescent intensity is significantly enhanced. From the results, we confirmed that the emission peak intensity of (Y,Sc)Al3(BO3)4:Gd3+ phosphors is stronger by a factor of about 1.5 compared to that of YAl3(BO3)4:Gd3+ phosphor to date.