Investigating synthetic routes for luminescent nanomaterials preparation

• Grant number: 07/05600-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): December 01, 2007
• Effective date (End): November 30, 2010
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Ana Maria Pires
• Grantee: Sabrina Aléssio Camacho
• Host Institution: Faculdade de Ciências e Tecnologia (FCT). Universidade Estadual Paulista (UNESP). Campus de Presidente Prudente. Presidente Prudente , SP, Brazil

Abstract

Luminescent materials containing rare-earth ions represent an important group of compounds formed by inorganic solids that, when doped with luminescent activator ions, can be applied as lasers active medium, fluorescent lamps, x-rays intensifier screens, scintillators, as well. Specifically in the case of luminescent nanomaterials, they have been widely applied as biological immunoassay reporters. When Er(III) and Yb(III) are the activators, they have the advantage of IR absorption and visible emission, avoiding the biological samples self-emission. Therefore, the improvement of synthetic routes as well as the preparation of different doped host lattices that could yield dispersed nanoparticles, are of great interest to the scientific point of view as well as the academic one. The aim of this work is the investigation of different methodologies to the preparation of matrices like RE2O3 and LiREO2 in order to result in nano-scaled materials that present suitable features for doping with Er(III) and Yb(III) ions. Preliminary investigation revealed that the phosphor Y2O3:Er,Yb can be obtained as an agglomerate of nanoparticles by using the Pechini Method or as a nanostructured like-sponge shape when combustion method is applied. So, for the preparation of monodispersed systems adequate for to be used as biological reporters, it is necessary to keep on searching for alternatively routes, essentially the ones that use conventional or modified sol-gel methodology.