Síntese e caracterização de vanadato de ítrio contendo íons Nd3+ a partir do processo Sol Gel

• Ano de defesa: 2017
• Autor(a) principal: Tanaka, Julio Tadashi
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade de Franca; Brasil; Pós-Graduação; Programa de Doutorado Ciências; UNIFRAN
• Palavras-chave em Português: Terras raras; Matriz hospedeira; YVO4; Fase pura; Fotoluminescência; CNPQ::CIENCIAS EXATAS E DA TERRA
• Link de acesso: https://repositorio.cruzeirodosul.edu.br/handle/123456789/394

In this work, an analysis of inorganic yttrium vanadate (YVO4) matrices prepared by the adaptation of the non-hydrolytic route Sol Gel process incorporated with different concentrations of Nd3+ ions was carried out and subjected to thermal treatment at temperatures of 600, 800 and 1000°C. The samples were characterized by X-ray diffractometry, RAMAN Vibrational Spectroscopy and Photoluminescence Spectroscopy. The work was divided into two stages with different objectives. In the first step, the focus was on optimizing the ideal concentration for the formation of the pure YVO4 phase, also called the host matrix. For this, several samples were synthesized containing different concentrations of yttrium and vanadium, maintaining the concentration of neodymium in 1% in mol in relation to vanadium. The second step consisted in the incorporation of different concentrations of Nd3+ ions (1% - 20% in mol, in relation to vanadium) in order to evaluate the influence of this ion in both the structural properties of the matrix and its photoluminescence. The results suggest that the sample containing the vanadium: yttrium: neodymium (59%: 40%: 1%) molar concentration showed the pure YVO4 phase. In the photoluminescence it was possible to observe that in spite of increasing the concentration of the Nd3+ ion there was a decrease in the luminescent properties of the matrix and through the X-ray diffraction it was observed that after the thermal treatments the crystalline structure of YVO4 was not significantly altered, however when treated at 600°C has characteristics of the vanadium oxide which has settled in the matrix after the increase of the treatment temperature.