ナノメディシンとナノテクノロジーのジャーナル

概要

Optical absorption and Photoluminescence studies in Gamma-irradiated nanocrystalline CaF2

C Pandu Rangappa and B.N. Lakshminarasappa

Calcium fluoride (CaF2) nanoparticles were synthesized by co-precipitation method and characterized by powder X-ray diffraction (PXRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM). Also, optical absorption (OA) and photoluminescence (PL) studies on gamma irradiated (?-rayed) CaF2 nanoparticles were carried out. The XRD patterns confirmed the cubic crystallinity of the samples and the particle size was found to be ?25 nm. The purity of the synthesized nanoparticles was confirmed by FTIR spectrum. The morphological features studied using SEM revealed the agglomerated and porous nature of nanoparticles. ?-rayed CaF2 nanoparticles showed a prominent absorption with a peak at ?360 nm besides three weak but well separated absorptions at ? 267, 442 and 510 nm. The various defect centers responsible for the absorption peaks were identified. The PL studies of samples showed strong emissions at ?396 nm and 425 nm. The observed PL emissions are attributed to defects created in nanocrystalline CaF2.