Enhanced red emission and high thermal stability from Bi3+/Eu3+ co-doped Ba3Y(BO3)3 phosphors for WLEDs application

A series of Bi3+/Eu3+ co-doped Ba3Y(BO3)3 red-emitting phosphors were successfully prepared by the combustion method. The crystal structure and photoluminescence properties of the as-prepared phosphors were investigated by X-ray powder diffraction, photoluminescence excitation and emission spectra. In this paper, the Bi3+ ion was employed as a sensitizer to improve the red emission intensity of Eu3+. The optimal doping concentration of Bi3+ was 1 mol%. The observed excitation broad bands centered at 300 nm confirmed Bi3+ ion doped into the Ba3Y(BO3)3 host. The red emission intensity of Eu3+ was significantly enhanced by doping a small amount of Bi3+. Furthermore, Bi3+/Eu3+ co-doped phosphor possessed admirable thermal stability (the emission intensity of studied phosphor at 423 K maintained 80.7% of the initial intensity at room temperature). The results manifest that Bi3+ ion is an efficient sensitizer for Eu3+ ion and Ba3Y(BO3)3: 24 mol% Eu3+, 1 mol% Bi3+ phosphors possess a great potential for applications in white LEDs.