Electrochemical atomic force microscopy study of proton conductivity in a Nafion membrane.
Phys Chem Chem Phys
; 9(21): 2735-43, 2007 Jun 07.
Article
em En
| MEDLINE
| ID: mdl-17627317
ABSTRACT
High membrane conductivity is one of the key parameters in polymer electrolyte fuel cell applications. We introduce an electrochemical atomic force microscopy method that provides simultaneously the surface topography of a Nafion 112 membrane and the conductivity of ion channels with an unprecedented resolution of ca. 10 nm. For given conditions, a large fraction of the channel ports is found to conduct exactly the same number of protons per unit time. This is taken as evidence for an optimum pore size and structure for proton conduction, or alternatively, for an efficient connectivity of the ion channel network, so that the same conductivity is measured at all exit pores. The time response following a potential step and the influence of the relative humidity on the transport properties is investigated. The method will be of relevance for tailoring the production technology to yield an optimised micromorphology, and it permits detailed tests of membrane models and provides data for theoretical modelling of proton conductivity.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Prótons
/
Polímeros de Fluorcarboneto
/
Microscopia de Força Atômica
/
Membranas Artificiais
Tipo de estudo:
Diagnostic_studies
/
Prognostic_studies
Idioma:
En
Revista:
Phys Chem Chem Phys
Ano de publicação:
2007
Tipo de documento:
Article