Synthesis, characterization and photophysic study of silver tungstates doped with rare earths

Abstract

Noble metal nanoparticle preparation is an interdisciplinary subject that is attracting intense research and development due to both the fundamental and applied scientific value of nanometer scale metals. Tungstates exhibit photoluminescence properties and antimicrobial action. In addition, silver materials exhibit high photocatalytic properties under visible light for dye degradation, bacteria destruction and electrocatalytic property. This research project aims to investigate the photoluminescent and photocatalytic properties of powders of pure silver tungstate (Ag2WO4) and doped with different rare earths (RE3+), (Ag2-3xRExWO4), using the method of coprecipitation, which is fast, does not need high temperatures or require sophisticated equipment and yields materials with homogeneous shape and size without secondary phases. Emission bands of some RE are easy to study in the visible region due to the structure of the energy levels, which enables their use in several applications. The luminescence properties of these ions, such as fine lines of absorption and emission, are due to electron transitions within the partially filled 4f layer which is protected from the environment by 5s and 5p external electrons. In addition, these elements have characteristic emissions and can be used as different luminescent devices. The powders will be characterized by X-ray diffraction (XRD), Rietveld Refinement, FT-Raman spectroscopy (Raman), Fourier transform infrared spectroscopy (FT-IR), Ultraviolet-visible spectroscopy (UV-vis), Scanning Electron Microscopy with Field Emission Gun (FEG-SEM), Photocatalysis and Photoluminescence spectroscopy (PL). (AU)