Desenvolvimento de um Sensor de Deformação a Base de Óxido de Grafeno Reduzido sobre Substrato Flexível

• Ano de defesa: 2021
• Autor(a) principal: Felipe Alencar Motta
• Orientador(a): Diogo Duarte dos Reis
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Fundação Universidade Federal de Mato Grosso do Sul
• País: Brasil
• Palavras-chave em Português: ciência dos materiais
• Link de acesso: https://repositorio.ufms.br/handle/123456789/4263

This work is based on the development and study about an strain sensor based on reduced graphene oxide (rGO) deposited on a flexible polydimethylsiloxane (PDMS) substrate. It also consists of studying the effect of the addition of biogenic silica nanoparticles to the rGO film and further investigation of the new sensor’s performance. To obtain biogenic nanosilica, calcination methods combined with acid leaching, and manual grinding combined with sonochemical erosion were used. The rGO sensors were produced by an automated spray-coating method, with subsequent termal-laser reduction. To carry out the deformation tests, an electromechanical equipment was developed which, mounted with a dial indicator, made it possible to automatically control the applied stretches. The morphological and chemical characterizations of the GO and rGO films were performed via scanning electron microscopy, energy dispersion X-ray spectroscopy, and X-ray diffraction. Electrical measurements showed that the produced rGO sensors exhibit high strain sensitivity, were the highest gauge factor (GF) observed was 185 in a deformation range of 0 to 4%, with nonlinear response. Sensors decorated with silica particles did not show a measurable response to this strain range, as they resulted in an insulating material, probably due to the excess of silica added to the GO matrix.