Estudo teórico de monocamada e bicamada de grafeno em superfície de óxido de háfnio amorfo
Nenhuma Miniatura disponível
Data
2015-04-30
Autores
Vitória Júnior, Moacir Cézar da
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Federal do Espírito Santo
Resumo
In this work, we have used the first principle calculations based on Density Funcional Theory (DFT) to investigate the interfaces between graphene monolayer (G) and graphene bilayer (BLG) on amorphous hafnium oxide (a-HfO2) surface. We have also considered carbon and oxygen vacancies in graphene sheets and amorphous hafnium oxide, respectively. In particular, we have studied different interfaces: (i) G(VC)/a-HfO2, (ii) G(VC)/a-HfO2(VO) and (iii) BLG(VC)/a-HfO2. From point of view energetic stability, our finds showed that the interfaces formation are an exothermic process, in the case (i) and (iii) ruled by van der Waals interactions. However, for interface (ii) the formation energy is two times higher than the others and presence of the chemical bonds was also observed. Moreover, from point of view structural, the presence of the substrate induce a corrugation on graphene sheets and the interfacial equilibrium distance between them is about 3,0 Å. Additionaly, our results showed that there is a total magnetic moment for interfaces (i) and (iii). Thus, our finds reveal that the structural, electronic and magnetic properties of the graphene sheets are very sensitive to presence of the substrate
Descrição
Palavras-chave
Graphene , Bilayer graphene , a-HfO2 , Magnetic moment , DFT , Grafeno , Funcionais de densidade , Momento magnético
Citação
VITÓRIA JÚNIOR, Moacir Cézar da. Estudo teórico de monocamada e bicamada de grafeno em superfície de óxido de háfnio amorfo. 2015. 70 f. Dissertação (Mestrado em Física) – Programa de Pós-Graduação em Física, Universidade Federal do Espírito Santo, Centro de Ciências Exatas e da Terra, Vitória, 2015