Optical properties of biosynthesized nanoscaled Eu2O3 for red luminescence applications

This contribution reports on the optical properties of biosynthesised E u 2 O 3 nanoparticles bioengineered for the first time by a green and cost effective method using aqueous fruit extracts of Hyphaene thebaica as an effective chelating and capping agent. The morphological, structural, and optical properties of the samples annealed at 500°C were confirmed by using a high-resolution transmission electron microscope (HR-TEM), x-ray diffraction analysis (XRD), UV–Vis spectrocopy, and photoluminescence spectrometer. The XRD results confirmed the characteristic body-centered cubic (bcc) structure of E u 2 O 3 nanoparticles with an average size of 20 nm. HR-TEM revealed square type morphology with an average size of ∼ 6 n m . Electron dispersion energy dispersive x-ray spectroscopy spectrum confirmed the elemental single phase nature of pure E u 2 O 3 . Furthuremore, the Fourier transformed infrared spectroscopy revealed the intrinsic characteristic peaks of E u − O bond stretching vibrations. UV–Vis reflectance proved that E u 2 O 3 absorbs in a wide range of the solar spectrum from the VUV–UV region with a bandgap of 5.1 eV. The luminescence properties of such cubic structures were characterized by an intense red emission centered at 614 nm. It was observed that the biosynthesized E u 2 O 3 nanoparticles exhibit an efficient red-luminescence and hence a potential material as red phosphor.