Estudo da influência dos parâmetros de síntese na preparação de nanopartículas de óxidos magnéticos de ferro por rota solvotérmica

Detalhes bibliográficos
Ano de defesa: 2013
Autor(a) principal: Silva, Fernando Barbosa de Freitas
Orientador(a): Oliveira, Cauê Ribeiro de lattes
Banca de defesa: Não Informado pela instituição
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Federal de São Carlos
Programa de Pós-Graduação: Programa de Pós-Graduação em Química - PPGQ
Departamento: Não Informado pela instituição
País: BR
Palavras-chave em Português:
Área do conhecimento CNPq:
Link de acesso: https://repositorio.ufscar.br/handle/20.500.14289/6576
Resumo: This work presents the development and the optimization of the synthesis of magnetic nanoparticles of iron oxides by the solvothermal method with benzyl alcohol using iron chlorides as metallic precursors in substitution to the iron (III) acetylacetonate, an expensive organometallic reagent an usually less available in laboratories. The synthesis parameters were studied and varied in order to obtain the higher possible yield of magnetite. During the synthesis optimization the necessity of a reducing agent to provide the charge balance of the magnetite s structure and the metallic iron, in a defined concentration, was used for this purpose. Furthermore, the use of urea as a precipitation agent was crucial to the increase in yield of magnetite once it decreased the acidity of the medium and induced the precipitation of the Fe2+ ions. The time of solvothermal method was also evaluated and it could be noticed that bigger times of solvothermal treatment lead to the increase in yield of magnetite, whose formation process follows the Ostwald rule, considering the stability of the phases in the set of conditions applied. Images of transmission electronic microscopy confirmed the nanometric scale of the particles. The polymerization of the benzyl alcohol was also studied to a better comprehension of the synthesis.