Luminescent Rare earth doped nanostructures materials: dynamics of the upconversion processes and applications as lasers, amplifiers and optical markers.

• Grant number: 11/08354-0
• Support Opportunities: Scholarships abroad - Research
• Start date: September 25, 2011
• End date: September 24, 2012
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Rogéria Rocha Gonçalves
• Grantee: Rogéria Rocha Gonçalves
• Host Investigator: Philippe Goldner
• Host Institution: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (FFCLRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Institution abroad: ParisTech, France

Abstract

This project aims to study the spectroscopic properties of materials based on luminescent lanthanide doped nanostructured oxides, for developing new nanostructured phosphors.The main objective is to study the dynamics of the upconversion processes in nanostructured oxide with low phonon energy, containing Ta2O5, Nb2O5, ZrO2, HfO2 or SnO2 doped with rare earth (Er3 +, Er3 + / Yb3 +, Tm3 +, Tm3 + / Yb3 + , Pr3 + and Pr3 + / Yb3 +). Planar waveguides, monoliths and powders will be prepared using the sol-gel method. Regarding on planar waveguides, they will be studied for lasers, amplifiers and power converters in solar cells applications. A spectroscopic study will be done including experimental and theoretical rate equations for levels involved in the upconversion processes, optimizing the chemical compositions for the required applications.Laser emission tests will be done mainly for the systems doped with Pr3 + and Pr3 + / Yb3 + (orange emission). Upconversion luminescence properties and their correlation with structural and morphological properties of nano-and microparticulate systems for application as optical markers in biological systems will also be studied. The correlation between optical properties and structural will be held depending on the composition, synthesis method, and the concentration of ions Ln3 + (Ln3 + = Er3 +, Tm3 +, Pr3 +, Er3 + / Yb3 +, Tm3 + / Yb3 +, Pr3 + / Yb3 +). Co-doping of these systems nanocomposites with Yb3 + ions will allow the study of energy transfer processes. (AU)