Structural configurations of thin dried polyaniline films on gold(111) from scanning tunneling microscopy

The early stages of growth of polyaniline films electrodeposited on Au were studied by conventional electrochemical techniques, X-ray diffraction and ex situ scanning tunneling microscopy (STM). From high resolution STM imaging it appears that the first step of polyaniline formation involves the ads...

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Detalhes bibliográficos
Autores: Vela, María Elena, Zubimendi, J. L., Ocón, P., Herrasti, P., Salvarezza, Roberto Carlos, Vázquez, Luís, Arvia, Alejandro Jorge
Formato: artículo
Estado:Versión publicada
Fecha de publicación:1996
País:Argentina
Recursos:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/127556
Acesso em linha:http://sedici.unlp.edu.ar/handle/10915/127556
Access Level:acceso abierto
Palavra-chave:Ciencias Exactas
Química
conducting polymers
thin polyaniline films
STM imaging
early stage structures
Descrição
Resumo:The early stages of growth of polyaniline films electrodeposited on Au were studied by conventional electrochemical techniques, X-ray diffraction and ex situ scanning tunneling microscopy (STM). From high resolution STM imaging it appears that the first step of polyaniline formation involves the adsorption of aniline monomers on Au(111) terraces leading to domains with hexagonal arrays involving a phenyl-phenyl distance in the range 0.70 nm ⩽ d ⩽ 1.0 nm. The second step corresponds to the initiation of the polymer growth yielding typically 10 × 10 nm<sub>2</sub> crystalline domains consisting of either 0.45 × 0.6 nm<sub>2</sub> rectangular arrays or 0.75 × 0.45 nm<sub>2</sub> arrays forming 120 ° angles. The crystalline domains coexist with highly disordered polymer domains. At advanced stages of growth, the formation of polymer fibers 2 nm in average width takes place leading to a full substrate coverage by a polymer deposit with an irregular surface.