Physical, structural and spectroscopic analysis of tellurite glass containing natural magnetite Fe3O4 nanoparticles

This paper reports the influence of the embedment of natural magnetite (Fe3O4) nanoparticles (NP) in tellurite glass containing Er3+ ions. Significance results on physical, structural and emission properties obtained from varying Fe3O4 nanoparticles in the glass network are well discussed. In this work, glass samples with composition (89-x) TeO2–10MgO – 1Er2O3 - (x)Fe3O4, (x = 0, 0.2, 0.4, 0.6 and 0.8 mol %) are prepared by melt quenching technique. X-ray diffraction shows that all samples exhibit amorphous nature. The TEM image shows the spherical shape of nanoparticles within an average diameter of ∼8 nm. Meanwhile, the HRTEM image of glass containing 0.4 mol % of Fe3O4 NPs shows the presence of Fe3O4 NPs with the interplanar distance of 2.2 Å and growth in the [ 113] direction. The density, molar volume and thermal parameters of Fe3O4 NPs dependence with thermal stability around 100 °C may be achieved. The IR spectra show the presence of structural group [TeO4] tbp and [TeO3] tp as confirmed by Raman spectroscopy. The indirect band gaps are ranged from (2.31–3.12) eV, reducing with the rising of Fe3O4 NPs. At lower concentrations of Fe3O4 NPs, the emission intensity of luminescence is enhanced while at higher Fe3O4 NPs the intensity is quenched due to the effect of spin-orbit coupling.