Title : Effects of erbium nanoparticles on luminescence properties of amorphous nano silicate borotellurite glasses
Abstract:
Four series of rare earth doped borotellurite silicate glass were prepared by melt quenching method. The first and second series are a quaternary erbium oxide and erbium oxide nanoparticles doped glass with chemical composition {[(TeO2)0.8 (B2O3)0.2]0.8 (SiO2)0.2}1-y (RE)y, y= 0.01, 0.02, 0.03, 0.04, 0.05 molar fraction and RE = Er2O3 /Er2O3 NPs, while the third and fourth series are multicomposition [{[(TeO2)0.8 (B2O3)0.2]0.8 (SiO2)0.2}0.99 (Ag2O)0.01]1-y (RE)y where y = 0.01, 0.02, 0.03, 0.04, 0.05 molar fraction. This research proposes to extract nano silica from the coconut shell and use it to synthesize a series of selected chemical composition of borotellurite silicate glasses doped with different concentration of Er2O3 nanoparticles (NPs) and doped with Ag2O in order to study their effects on the physical, structural, optical and thermal properties. This will go a long way in turning waste into wealth. Addition of Ag2O into the glass composition modifies the optical properties of the glass system. A novel type of glasses containing rare earth ions and silver ions has recently emerged and already attracted significant attention, the reason for such interest lies in the efficient enhancement of the fluorescent properties in rare earth doped glasses when appropriate silver ions is introduced to it. Results of X-ray diffraction (XRD) confirmed the amorphous nature of the glass. The X-ray fluorescence (XRF) verified the achievement of 48.6% of silicate from coconut shell. Fourier transform infrared (FTIR) has revealed the basic structural units such as TeO4, TeO3, BO4, BO3, Si-O-Si and O-Si-O in the glass system. The presence of erbium nanoparticles in the second and fourth series was verified from transmission emission microscopy (TEM) and the size of the nanoparticles were recorded within the range of 25 – 28 nm and 41 – 50 nm. The differential scanning calorimetry (DSC) measurements indicate a good thermal stability of borotellurite silicate glasses with the values of Ts > 100 oC, and the transition temperature, Tg in all the glass series are found to increase from 437 to 511 oC, 447 to 498oC, 452 to 482 oC and 469 to 495 oC with the increasing dopants concentrations in all the four glass series.
