Photoluminescence properties of LiF Bismuth Silicate glass

The sample (60-X) Bi2O3-30SiO(2)-XLiF where X=10, 15, 25 were prepared by conventional melt quenching method. X-ray diffraction pattern conformed the amorphous nature of the prepared sample and a broad peak at 2 theta=30 degrees. The Raman spectra confirmed that the Bi can exist both network former (BiO3 pyramidal) and network modifier (BiO6 octahedral) in the glass matrix. The samples showing broad absorption at 470nm is due to the presence of Bi2+ ions, because of increasing optical basicity the absorption edge of the sample is blue shifted. The photoluminescence spectra of the glass under 350nm excitation are showing two main peaks at 430nm and 630 nm due to Bi3+ and Bi2+ respectively and 25 LBS glass showing yellow, 15LBS showing near bluish white and 10LBS showing blue luminescence. The color purity and correlated color temperature are also calculated.