Nanocomp?sitos de matriz polim?rica e cargas h?bridas baseadas em grafeno decorado com nanopart?culas met?licas

• Ano de defesa: 2021
• Autor(a) principal: Maraschin, Thuany Garcia
• Orientador(a): Basso, Nara Regina de Souza
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Pontif?cia Universidade Cat?lica do Rio Grande do Sul
• Programa de Pós-Graduação: Programa de P?s-Gradua??o em Engenharia e Tecnologia de Materiais
• Departamento: Escola Polit?cnica
• País: Brasil
• Palavras-chave em Português: Grafeno; Nanopart?culas Met?licas; Sputtering; Polietileno
• Palavras-chave em Inglês: Graphene; Metallic Nanoparticles; Sputtering; Polyethylene
• Área do conhecimento CNPq: ENGENHARIAS
• Link de acesso: http://tede2.pucrs.br/tede2/handle/tede/10076

Graphene and metallic nanoparticles (MNPs) hybrid systems have been studied due to their conductive, magnetic, and adsorbent properties. However, the deposition of MNPs on graphene in powder form, without the need for substrates to stabilize these compounds, is poorly explored. Thus, this work presents an effective method for obtaining hybrid reduced graphene oxide (rGO) nanoparticles decorated with 5 % and 10 % of Ni, Fe and permalloy. The few layers rGO was obtained from the oxidation route followed by thermal reduction. MNPs were deposited by the sputtering technique. The TEM showed nanoparticles of Ni, Fe and permalloy evenly distributed throughout the rGO. TGA and RBS results confirm the amount and composition of MNPs deposited. The interaction between MNPs and rGO was studied by FT-IR. According to the XPS result, the hybrids have a decrease in the relative amount of oxygen regarding the rGO. The addition of MNPs generated ferromagnetic properties in the MNPs/rGO samples, and the electrical conductivities values were doubled with the addition of 10% Ni and Fe, and tripled in the systems containing permalloy. The addition of MNPs/rGO systems into polyethylene (PE) was also evaluated in this work. PE-MNPs/rGO nanocomposites were obtained by in situ polymerization. The addition of 0.1 % and 0.5 % of the hybrids in the PE matrix did not change the catalytic activity, thermal properties, and degree of crystallinity. PE-MNPs/rGO exhibited electrical and diamagnetic insulating properties. Based on these results, a promising route to obtain graphene decorated with MNPs was obtained for the first time from the sputtering technique using powdered graphene. The approach described in this work is promise for the preparation of hybrid rGO/MNP materials for application in catalysts, electrodes, filters and in electromagnetic shielding.