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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Graphene healing mechanisms: A theoretical investigation

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Autor(es):
Botari, Tiago [1] ; Paupitz, Ricardo [2] ; da Silva Autreto, Pedro Alves [1] ; Galvao, Douglas S. [1]
Número total de Autores: 4
Afiliação do(s) autor(es):
[1] State Univ Campinas UNICAMP, Dept Appl Phys, BR-13083859 Campinas, SP - Brazil
[2] Univ Estadual Paulista UNESP, Dept Phys, BR-13506900 Rio Claro, SP - Brazil
Número total de Afiliações: 2
Tipo de documento: Artigo Científico
Fonte: Carbon; v. 99, p. 302-309, APR 2016.
Citações Web of Science: 12
Resumo

Large holes in graphene membranes were recently shown to heal, either at room temperature during a low energy STEM experiment, or by annealing at high temperatures. However, the details of the healing mechanism remain unclear. We carried out fully atomistic reactive molecular dynamics simulations in order to address these mechanisms under different experimental conditions. Our results show that, if a carbon atom source is present, high temperatures can provide enough energy for the carbon atoms to overcome the potential energy barrier and to produce perfect reconstruction of the graphene hexagonal structure. At room temperature, this perfect healing is only possible if the heat effects of the electron beam from STEM experiment are explicitly taken into account. The reconstruction process of a perfect or near perfect graphene structure involves the formation of linear carbon chains, as well as rings containing 5, 6, 7 and 8 atoms with planar (Stone-Wales like) and non-planar (lump like) structures. These results shed light on the healing mechanism of graphene when subjected to different experimental conditions. Additionally, the methodology presented here can be useful for investigating the tailoring and manipulations of other nano-structures. (C) 2015 Elsevier Ltd. All rights reserved. (AU)

Processo FAPESP: 13/08293-7 - CECC - Centro de Engenharia e Ciências Computacionais
Beneficiário:Munir Salomao Skaf
Linha de fomento: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs
Processo FAPESP: 14/15521-9 - Propriedades estruturais e eletrônicas de sistemas moleculares e bidimensionais
Beneficiário:Ricardo Paupitz Barbosa dos Santos
Linha de fomento: Auxílio à Pesquisa - Regular