A novel blue-emitting phosphor Gd4.67Si3O13:Bi3+ for near-UV LEDs

A novel blue-emitting phosphor Gd4.67Si3O13:Bi3+ has been synthesized by a conventional high-temperature solid-state method. X-ray diffraction, and photoluminescence spectra were used to characterize the as-synthesized phosphor. Upon 370 nm excitation, the Gd4.67Si3O13:Bi3+ phosphor exhibits a broad emission band centered at 455 nm. Monitoring the 455 nm emission, the Gd4.67Si3O13:Bi3+ phosphor shows an intense broad absorption band ranging from 200 to 400 nm. The energy transfer mechanism between Bi3+ ions has been discussed, which is demonstrated to be dipole-dipole interaction. The critical concentration is 3 mol% and the critical distance is found to be 25.7 angstrom. The thermal stability and the CIE coordinates are also investigated in this work. The CIE coordinates of the Gd4.67Si3O13:Bi3+ phosphor upon 370 nm excitation are (0.141, 0.096). All the results indicate that the blue-emitting phosphor Gd4.67Si3O13:Bi3+ has potential applications for white LEDs.