Studies of optical and structural properties of rare earth containing luminescent garnets

• Grant number: 25/21871-7
• Support Opportunities: Scholarships abroad - Research Internship - Scientific Initiation
• Start date: December 01, 2025
• End date: February 15, 2026
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Marcelo Nalin
• Grantee: Breno Cavalheiro de Siqueira
• Supervisor: Marc Dussauze
• Host Institution: Instituto de Química (IQ). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil
• Institution abroad: Université Bordeaux 1, France
• Associated to the scholarship: 25/00895-5 - Synthesis and characterization of rare-earth garnets for applications as scintillators, BP.IC

Abstract

This project aims to obtain garnets containing rare earth ions (Ce³+ and Gd³+) through the controlled precipitation of the desired crystalline phase, using special glass compositions as a reaction medium. Glasses with the composition GeO2-PbO-Bi2O3-Ga2O3-TR2O3 (where TR = Ce2O3 or Gd2O3) are melted at temperatures close to 1200 °C. After complete homogenization, controlled cooling is carried out, during which phase separation and the formation of TR3Ga5O12 single crystals occur. This new methodology for preparing gallium garnets is unprecedented and was recently developed by our research group. Thus, the main objectives of this project are to synthesize luminescent garnets with applications as scintillators, targeting the synthesis of a scintillator with a very fast decay time and the development of garnets exhibiting persistent luminescence, for which the cerium-containing phase must be co-doped with Cr³+. All synthesized materials will be characterized in terms of their structural, thermal, and optical properties, with particular emphasis on luminescent properties. In this internship we will focus on the analysis of the garnets using micro-3D-spectroscopic techniques which will allow the comprehension of the optical and structural properties of the new materials.