Citric Acid Assisted Sol-Gel Synthesis and Photoluminescence Characteristics of CaAl1.8Y0.2-xO4: xTb Nanoparticles

Abstract

A novel green light emitting nano-sized phosphor, Tb3+ doped CaAl1.8Y0.2-xO4:xTb3+ was synthesized using citric acid assisted sol-gel process. Comparing with traditional material processing techniques, sol-gel process is a relatively simple method. The advantages of low temperature solution base process have been exploited to produce nano particles and the phase transformation involved in the pure homogeneous mixture formation. Synthesis conditions such as calcinations temperature and citric acid concentration are varied in order to determine the exact optimum conditions for synthesizing CaAl1.8Y0.2-xO4:xTb3+ nano particles with superior optical properties and smaller particle size. The nano crystals obtained through sol-gel method was characterized by using scanning electron microscopy (SEM), X-ray diffraction (XRD) technique and photoluminescence (PL) spectra. The predominant green colour from magnetic dipole transition 5D4 → 7F5 of Tb3+ was located at 543 nm.