Desenvolvimento de um material condutivo baseado em flocos de grafite e poliestireno com aplicação eletroquímica

• Ano de defesa: 2020
• Autor(a) principal: Luz, Luiz Fernando Gabriel
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Uberlândia; Brasil; Programa de Pós-graduação em Química
• Palavras-chave em Português: Eletrodo; Polímero; Poliestireno; Flocos de carbono; Sensores; Electrode; Polymer; Polystyrene; Carbon flakes; Sensors; CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA::FISICO-QUIMICA::ELETROQUIMICA
• Link de acesso: https://repositorio.ufu.br/handle/123456789/28963; http://doi.org/10.14393/ufu.di.2020.314

In electrochemical processes there are different types of materials and techniques that can be used to carry out experiments. Basically, the main resource for these materials is electrical conductivity. Consider this property to be present in metals, these highlights, since it is possible to make changes or just use the electron as a reagent already makes it possible to use electrochemical techniques. The knowledge and mastery of different types of materials and techniques leads to the production of new sensors, which can be standardized using their reproducibility. Accept the user-friendly system, the sensors are made a useful tool, with sensitivity and the selection of characteristics essential for them. In view of the above, this work uses polystyrene, which is a non-conductive polymer, but low cost, as a binder for graphite sheets, which is a material with conductive properties. This mixture was tested in various proportions, with the main results being electronic materials in the form of discs, containing 80 or 85% graphite sheets. Mechanical polishing was carried out on the surface of this material and then electrochemical polished by cyclic voltammetry in sulfuric acid, using the homogenization of the surface and the removal of impurities. Evaporation tests of the solvent were carried out with a reduction in the electrical resistance of the material, using an anionic potassium ferri/ferrocyanide probe to evaluate the electronic transfer and reversibility studies, which demonstrated satisfactory results. As morphological characterizations of the material were made through SEM, TGA and DSC. After these studies, the electronic material was used for the incorporation of a DNA probe and the detection of a complementary target, applying its applicability as a bioelectrode, being observed the representative difference between the electrochemical signals of probe and target.