Modificação superficial de fosfatos de terras raras com funcionalização de ligantes orgânicos para aumento de eficiência luminescente na região do visível

• Autor(a) principal: Lopes, André Luis
• Data de Publicação: 2022
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UFSCAR
• Texto Completo: https://repositorio.ufscar.br/handle/ufscar/16786
• topic: Terras raras; Fosfato de Praseodímio; Propriedades luminescentes; Rare Earths; Luminescent properties; Praseodymium Phosphate; CIENCIAS EXATAS E DA TERRA::QUIMICA

Introduction: Seeking a greater understanding of the interaction of light with matter, in order to develop new materials that present desirable properties and characteristics, this work sought to associate the unique luminescent characteristics of the rare earth Dy3+ and Pr3+ ions with a phosphate host matrix. In order to obtain a DyPO4/PrPO4 heterostructure, so that the resulting emission of the product was a complementation of the individual emissions, 7 different samples were synthesized varying the Dy:Pr ratio (mol/mol) in the host matrix and 7 other samples varying the same proportions, but these functionalized with Hhpa, where it was expected to observe the antenna effect of the organic ligand. Methods: The synthesis method used was through microwave-assisted hydrothermal coprecipitation, followed by functionalization with Hhpa for the samples relevant to the study. The characterizations were in charge of XRD, FT-IR, Raman, SEM and FL analyses. Results: In view of the spectroscopic data that were obtained for the synthesized samples, it is concluded that the chosen synthesis method was efficient in terms of the structural and morphological properties of the product, bringing interesting considerations about the desired and obtained heterostructure. Regarding the luminescent properties, for the samples functionalized with Hhpa, which were expected to observe the antenna effect, the resulting emission intensities increased by a factor of 10^4, corroborating the general objective to be achieved. Finally, the samples functionalized with Hhpa emit in the region of a deep blue and with greater intensities compared to the non-functionalized ones.