Study of the optical and luminescent properties of earth-alkali (MgF2, CaF2, SrF2, BaF2) Fluorophosphate glass and glass-ceramic doped with lanthanide ions

• Grant number: 19/16115-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2019
• End date: December 18, 2021
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Danilo Manzani
• Grantee: Leandro Olivetti Estevam da Silva
• Host Institution: Instituto de Química de São Carlos (IQSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

This research project proposes the systematic study about the structural, thermal, optical and luminescent properties of glass and glass-ceramics based on fluorophosphate, focused on photonic applications by controlling its physical and chemical properties to maximize the efficiency of the luminescence processes by means of decreasing the non-radiative decay by minimizing the structure's phonon energy, local symmetry around the lanthanide ions and the presence of hydroxyl groups. Using a matrix based in lead pyrophosphate and transition metal oxides, such as niobium oxide, the phonon energy will be decreased by inserting the earth-alkali fluorides MgF2, CaF2, SrF2 and BaF2 to the composition. Eu3+, Tm3+ doped and Yb3+ co-doped glasses will be explored, focusing on the study of the up-conversion mechanisms responsible for Tm3+ emissions when sensitized by Yb3+ for blue light generation and infrared emissions. Transparent glass-ceramics will be produced by controlled heat treatment programs above the glass transition temperatures of the compositions and the effect of nanocrystal precipitation on the matrix to the luminescence will be investigated. The glass and glass ceramics will be characterized by thermal (DSC), structural (Raman, FT-IR), morphological (SEM and MET) and optical (absorption, transmission, luminescence) techniques.