Synthesis and characterization of Dy-doped Zn2SiAl2O4 nanophosphor for color modulation in advanced lighting systems

Nanoparticles of Zn2SiAl2O4 infused with Dy3+ were produced through a traditional co-precipitation approach. We investigated the particles' structural attributes and physical characteristics using tools such as X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), UV–Vis absorption spectroscopy, and photoluminescence (PL) spectrometry. The XRD outcomes validated the crystalline nature of the nanoparticles and showed the effective replacement of Dy3+ ions in the place of Zn2+ ions within the matrix and with increasing Dy concentration from 0.5 % to 1.25 %, the crystallite size decreased from 84 nm to 53 nm. The SEM visuals offered clarity on the shape, dimension, and spread of these particles. FTIR analysis further confirmed the composition and structure of the nanoparticles by identifying the chemical bonds and functional groups. UV–visible absorption spectroscopy revealed increase in the optical energy bandgap from 4.45 eV to 4.55 eV with increasing Dy3+ content, indicating potential for optical applications. The photoluminescence spectrometry results featured a prominent transition at approximately 646 nm, suggest that the phosphor has the capability to function as a vivid yellow light emitter and demonstrate their potential for application in optoelectronics, photonics, and luminescent materials

Optical Properties of Mg, Fe, Co-Doped Near-Stoichiometric LiTaO3 Single Crystals

Mg, Fe co-doped near-stoichiometric lithium tantalite (SLT) single crystals were grown by employing the zone-leveling Czochralski (ZLCz) technique. The optical properties, holographic parameters, as well as the composition of the grown crystals were measured. It was found that the Li/Ta ratio decreased with the doping of Mg and Fe ions. A red shift was observed in absorption spectrum for the Mg, Fe co-doped crystals compared to the undoped and Mg-doped ones. The effect of the iron ions (Fe2+ and Fe3+) was further discussed based on the specified absorption bands. Moreover, the occupation mechanism for the defects was discussed by using the IR absorption spectrum, which was attributed to the FeTa3− defects in the highly Fe-doped crystal. In addition, the holographic parameters were also found to be improved with a higher Fe/Ta ratio in the crystals