Physical, structural and optical properties of erbium doped tellurite glass with copper oxide nanoparticles embedment

Abstract

Two series of glass with composition of (70–x)TeO2 – 10ZnO – 10MgO – 10 Na2O – (x)Er2O3 where 0.0 =x = 2.0 mol% and (69–y)TeO2 – 10ZnO – 10MgO – 10Na2O – 1Er2O3 – (y)CuO where 0.05 = y = 1.50 mol% are prepared using melt quenching technique. The physical properties are measured in terms of glass density, ionic packing density and molar volume while the glass hardness is determined by using Vickers Microhardness. The amorphous nature of the glass is determined by X-ray Diffractometer (XRD). The occurrence of copper oxide nanoparticles (CuO NPs) is verified by using High-Resolution Transmission Electron Microscopy (HRTEM). The structural and optical properties are characterized by using Fourier Transform Infrared (FTIR), UV-Visible-NIR spectrophotometer and Photoluminescence (PL) spectrometer, respectively. The glass density, molar volume, ionic packing density and hardness are found in the range of (4.799 – 4.951) g cm-3, (26.575 – 27.202) cm3 mol-1, (0.457 – 0.467) and (235 – 349), respectively. It is found that all glasses are amorphous in nature while the presence of CuO NPs with lattice spacing 0.23 nm at (111) plane is verified by HRTEM analysis. FTIR spectrum exhibited three major bands which are attributed to Te – O – Te, TeO4 and TeO3 in the range of 400 – 4000 cm-1. Meanwhile, UV-Visible-NIR spectra reveal nine absorption peaks centered at about 407, 449, 488, 522, 545, 652, 799, 976 and 1530 nm originating from 4I15/2 to 2H9/2, 4F5/2, 4F7/2, 2H11/2, 4S3/2, 4F9/2, 4I9/2, 4I11/2 and 4I13/2 transitions respectively. Down-conversion emission spectra under 380 nm excitations shows four peaks centered at about 408, 530, 550, and 660 nm allocated to 4F3/2 ? 4I15/2, 2H11/2 ? 4I15/2, 4S3/2 ? 4I15/2 and 4F9/2 ? 4I15/2 transition. Meanwhile, up-conversion emission spectra under 980 nm excitations shows peaks three centered at about 530, 550, and 660 nm allocated to 2H11/2 ? 4I15/2, 4S3/2 ? 4I15/2 and 4F9/2 ? 4I15/2 transition