Effect of the Trivalent Erbium Concentration on the Luminescent Properties of TiO2 Er3+ Composites

Abstract

In this work we synthetized Er3+-doped TiO2 composites by means of the sol-gel method aiming to find the most emissive sample. For this optical characterization we used three samples with different erbium concentration (0.5, 1.0 and 3.0 wt%). We measured and compared the corresponding photoluminescent emission spectra using an excitation wavelength at 350 nm. Emission peaks in the green region associated with Er3+ transitions 4S3/2  4I15/2 and 2H11/2 4I15/2 were found. The sample TiO2Er1 (1.0 wt%) had the highest intensity profile and therefore we performed further characterizations on this composite. We measured its emission spectrum in the infrared region using the same excitation at 350 nm and we found emission peaks associated with transitions 4I11/2  4I15/2 and 4I13/2  4I15/2. We verified the morphology and structural properties of this material with Raman spectroscopy, X-Ray Diffraction and Scanning Electronic Microscopy. We consider that this composite could have promising potential in applications in communications.