Photoluminescence characteristics of sol-gel materials prepared from bimetallic erbium alkoxides coordinated by Al or Ti

Abstract

Er3+-doped Al2O3-SiO2 and TiO2-SiO2 powders were prepared by the sol-gel process using bimetallic erbium isopropoxides coordinated with Al or Ti. The local environment surrounding Er3+ ions was controlled orderly at the precursor stage. The phase development of two different systems as a function of temperature was characterized by XRD, and the amount of OH groups remaining within the samples was investigated by a Fourier-transformed infrared spectrometer with increasing annealing temperatures. The photoluminescence spectra and lifetimes of two systems annealed at different temperatures were measured and discussed. The strong emission and long lifetime were observed in Er3+-doped Al2O3-SiO2 system, ascribed to the homogeneous distribution of Er3+ ion