A novel green-to-yellow emitting phosphor: BaSi2SN2.67:Eu2+ for potential application in UV-LEDs

A novel compound BaSi2SN2.67 (BSSN) has been obtained from BaS and Si3N4 by a facile solid state method at 1100 degrees C in NH3 flow. X-ray powder diffraction pattern shows a pure phase of hexagonal BSSN. The lattice parameter a is 0.7504 nm and c is 0.6480 nm. Neither trace of raw materials or other compounds is presented in the pattern. A novel phosphor Eu2+ doped BSSN shows intense absorption in near UV region indicating potential application in UV-LEDs. It emits green-to-yellow photoluminescence (PL) with maximum at 523 nm which shows a large red shift compared to the identified phosphor BaSi2O2N2:Eu2+ (499 nm). Additionally, the full width high maximum (FWHM) of the emission band of BSSN:Eu2+ is 70 nm that is much larger than that of BaSi2O2N2:Eu2+ (35 nm). The dependence of PL intensity of Eu2+ on the doping concentration has been investigated. (C) 2013 Elsevier B.V. All rights reserved.