Combustion synthesis and photoluminescence study of UV emitting LaBaB₉O₁₆ phosphors

The borate phosphor LaBaB₉O₁₆ doped with Ce³⁺ ion intentionally and successfully synthesized using solution combustion rout using metal nitrates as precursors and urea as fuel. The phosphors were characterized by X-ray diffraction (XRD), Scanning electron microscopy and photoluminescence spectroscopies. The XRD patterns of the phosphor confirmed the successful crystallization of LaBaB₉O₁₆. The average crystallite size calculated using the Debye Scherer equation. The PL excitation spectra of LaBaB₉O₁₆ exhibited broad spectra peaking at 275 nm. Upon excitation with ultraviolet (UV) radiation at 274 nm the phosphor exhibited a broad band UV emission peaking at a wavelength of 335 nm corresponding to the 4f⁰5d¹− 4f¹ transition of the Ce³⁺ ion. Moreover the influence of concentration of Ce³⁺ ion on luminescence properties has also been studied. Optimum concentration of Ce³⁺ ions in the prepared phosphor was found to be 0.05 mol. For this concentration the critical distance R₀ was calculated to be 22.04 Å. Finally, the Stokes shift for the synthesized phosphor was calculated to be 6512 cm^− 1 using corresponding excitation and emission.