Novel blue-emitting KBaGdSi₂O₇:Eu²⁺ phosphor used for near-UV white-light LED

Novel blue-emitting KBaGdSi₂O₇:Eu²⁺ phosphors were designed and synthesized through solid-state reaction method. The structural properties, concentration, and temperature-dependent luminescence behaviors of these phosphors were investigated in detail in this paper. Studies revealed that KBaGdSi₂O₇:Eu²⁺ phosphors have an intense absorption in the broad wavelength ranging from 250 to 400 nm that is suitable for the commercial near-UV LED, and give out intense blue light peaked at 475 nm with a full-width half-maximum of 75 nm. The crystallographic information of KBaGdSi₂O₇ phase is revealed from XRD pattern by Rietveld refinement. Band gap is derived to be 3.93 eV through diffuse reflection spectra through Kubelka Munk function. The concentration quenching mechanism is identified as the dipole–dipole interaction. Moreover, the thermal quenching experiment was also conducted and the activation energy is calculated as 0.3069 eV, which indicates this novel KBaGdSi₂O₇:Eu²⁺ phosphor has good thermal stability. These properties exhibit its potential commercial application for near-UV white-light LEDs (w-LEDs).