Luminescence of thin films of titanium dioxide and quinoline derivatives, and test for organic-inorganic LED

• Grant number: 25/04274-5
• Support Opportunities: Scholarships abroad - Research Internship - Scientific Initiation
• Start date: June 16, 2025
• End date: August 15, 2025
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Luis Vicente de Andrade Scalvi
• Grantee: Natalia Carli de Oliveira
• Supervisor: Xavier Mateos Ferre
• Host Institution: Faculdade de Ciências (FC). Universidade Estadual Paulista (UNESP). Campus de Bauru. Bauru , SP, Brazil
• Institution abroad: Universitat Rovira i Virgili (URV), Spain
• Associated to the scholarship: 22/12998-5 - Investigation of the oxide semiconductor TiO2, as thin films, and combination with quinoline derivatives, aiming to technological applications, BP.IC

Abstract

The work currently carried out in Brazil (UNESP, Bauru) involves two materials, an inorganic semiconductor: titanium dioxide (TiO2), with n-type conductivity, and an organic compound: the quinoline derivative (QD), which may present p-type conduction, depending on the groups attached to the main chain. The QD has interesting electro-optical properties, such as luminescence in the blue range and electron acceptor character. The studies that we have carried out with these materials up to now have been conducted in the form of thin films, focusing mainly on their optical and electronic properties. When coupled in the form of a heterostructure, they presented a rectifying electrical behavior, that is, there was the formation of a p-n junction (diode). The work proposal in Tarragona includes carrying out structural and morphological measurements, such as X-ray diffraction, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX), in addition to optical measurements, such as time-resolved photoluminescence spectroscopy and temperature dependence of light emission. These measurements will be done in QD films as well as rare-earth doped TiO2. Moreover, tests for our organic-inorganic device will be carried out. These experiments will be fundamental for the understanding of electrical transport properties in these samples and to the design of opto-electronic devices. The supervision in Tarragona will be done by Prof. Xavier Mateos Ferré, who has great experience with complex oxide materials and their physical characterization under the structural, optical and spectroscopic points of view.