Optical properties improvement of dysprosium doped tellurite glass via silver/titanium nanoparticles coembedment

Abstract

In this study, some dysprosium ions (Dy3+)-doped zinc-magnesium tellurite glasses with the co-embedment of silver nanoparticles (ANPs) and titanium nanoparticles (TNPs) were prepared using the standard melt quenching method. The compositions of the glass series I and II were (69.5-x)TeO2-20ZnO-10MgO-0.5Dy-(x)AgCl (0 = x = 1.0 mol%) and (69.3-y)TeO2-20ZnO-10MgO-0.5Dy-0.2AgCl–(y)TiO2 (0 = y = 0.6 mol%), respectively. As-quenched glass samples were thoroughly characterized using different analytical techniques. The improvement in the optical, physical and structural properties of these glasses due to the co-embedment of two types of nanoparticles was determined. The optimum glass sample from both series was chosen to determine the influence of ANPs/TNPs inclusion on the optical, physical and structural characteristics. The ultraviolet-visible-infrared (UV-Vis-NIR) optical spectral analyses of the glass series I revealed an improvement in the absorption properties due to the addition of ANPs, while the glass series II (with ANPs and TNPs) showed a decrease in the absorption. Both glass series displayed six absorption bands due to the electronic transition from the ground state to various excited states of Dy3+. The Judd-Ofelt intensity parameters, O? (?=2, 4, 6) of the glasses were evaluated from the measured absorption spectra. The X-ray diffraction patterns of the as-quenched samples verified their amorphous nature. The high resolution transmission electron microscope (HRTEM) images revealed the presence of individual ANPs, TNPs and combined ANPs/TNPs in the glass matrix. The energy dispersive X-ray (EDX) spectra and mapping of the prepared glasses exhibited their appropriate elemental compositions. The incorporation of the ANPs/TNPs into the glasses was found to enhance their Raman and Fourier transformed infrared (FTIR) spectral intensities. The up-conversion and downconversion photoluminescence spectra of both glass series showed three prominent emission bands at 482 nm (blue: 4F9/2 ? 6H15/2), 574 nm (yellow: 4F9/2 ? 6H13/2), and 664 nm (weak red: 4F9/2 ? 6H11/2). In addition, the values of O? displayed the trend of O2>O6>O4 for the glass containing 0.1 mol% of TNPs, while all other glasses showed the trend of O2>O4>O6. The obtained results suggested that the optical properties of the Dy3+-doped zinc-magnesium tellurite glasses can be improved via the co-embedment of ANPs/TNPs compared to one type of NPs embedment. It is asserted that the proposed glass system may be useful for the development of optoelectronic and solid-state devices needed for different applications.