INTERAÇÃO DE GRAFENO E METALOFTALOCIANINA: UMA ABORDAGEM DE PRIMEIROS PRINCÍPIOS

• Autor(a) principal: Schwarz, Stefanie Camile
• Data de Publicação: 2014
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional Universidade Franciscana
• Texto Completo: http://www.tede.universidadefranciscana.edu.br:8080/handle/UFN-BDTD/530
• topic: Grafeno, metaloftalocianinas, teoria do funcional da densidade, estudo de primeiros princípios.; Graphene, metallophthalocyanines, density functional theory, first principles study.; Biociências e Nanomateriais

Nanotechnology is a term used to describe the studies that intend to understand and control the matter at the nanoscale. On this scale, the structures can present different chemical and physicochemical properties and behaviors from those observed in macro or microscales. Among the nanomaterials, graphene is highlighted due to its bidimensional structure, as well as its physical and chemical properties. It possesses promising technological and biomedical applications. The combination of graphene and molecules of biological interest, such as phthalocyanines (Pc), is a major focus of studies for the development of systems for nanobiotechnology. Thus, in this work, the interaction of graphene with Fe, Mn and Cu metallophthalocyanines (MPc) is studied, by chemical and physical adsorption, through ab initio calculations based on the density functional theory formalism, using the SIESTA computational code. First of all, it was evaluated the isolated Pc behavior, as well as its interaction with the Fe, Mn and Cu transition metals. It was observed that the metals interact strongly with the Pc forming stable complexes. Subsequently, it was studied the interaction of graphene and the MPc in order to understand the energetic, magnetic and structural properties of these structures to support the use of these nanomaterials in future biomedical applications. The results show that it is possible to observe that depending on the MPc metal, different values for the charge transfer as well as for spin polarization between the systems may occur, but all the systems present a weak interaction, via physical adsorption, between graphene and the MPc.