Synthesis and photoluminescence properties of BaGeTeO6:Eu3+ red-emitting phosphor for n-UV Light Emitting Diodes

Novel red-emitting phosphors based on germanium tellurate host matrix, BaGeTeO6 doped with Eu3+ were prepared by solid-state reaction. X-ray diffraction analysis revealed that the phosphors consisted of hexagonal structure. The as-prepared BaGeTeO6:Eu3+ phosphors showed strong red emission at 610 nm corresponding to the D-5(0)-F-7(2) transition of Eu3+ upon 394 nm near UV wavelength. The optimal doping concentration of BaGeTeO6:xEu(3+) was 5% and the critical distance of energy transfer between the Eu(3+)ions was estimated to be about 17 angstrom. Temperature dependence of the Eu3+ emission intensity measured at T = 300-480 K was successfully analyzed. Due to their CIE coordinates with high color purity, BaGeTeO6:Eu3+ phosphors have potential application in the fabrication of WLED.