Synthesis and spectroscopic study of calcium and magnesium disilicate doped with divalent europium and/or manganese for PC-LEDs

• Grant number: 23/04576-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2023
• End date: December 31, 2023
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Marian Rosaly Davolos
• Grantee: Juliana de Macedo Tavares
• Host Institution: Instituto de Química (IQ). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

The continuous advancement of materials to manufacture light-emitting diodes (LEDs) requires studies of systems to optimize their parameters for the development of these devices. LEDs can currently be manufactured aiming white light illumination, also known as WLEDs. However, the most commercialized LED contains a blue light emitting LED, InGaN, covered by a yellow light emitting luminophore, Y3Al5O12:Ce3+, which produces a cold white light, which can be harmful, especially at night, deregulating the human circadian cycle. Therefore, we seek to manufacture a prototype capable of producing warm white light by combining a commercial LED chip that emits in the ultraviolet or blue region and the Ca2MgSi2O7:Eu2+,Mn2+ luminophore. The choice of dopants is due to the emission of red light by Mn2+ and green by Eu2+, which also acts as a sensitizer transferring energy to Mn2+. The characterization of the structure, morphology and luminescence of the synthesized materials will use the techniques of X-ray diffraction, infrared vibrational spectroscopy, vibrational Raman scattering spectroscopy, diffuse reflectance in the UV-visible spectral region, photoluminescence spectroscopy in the steady state and resolved in the time, emission quantum yield measurements, emission thermal extinction measurements, X-ray spectroscopy, and scanning electron microscopy.