Tipo
Artigos em Conferência
Tipo de Documento
Poster without full or short paper
Título
Ellipsometric study of the redox conversion for low temperature PEDOT:PSS films
Participantes na publicação
Daniel R. Santos (Author)
FACULDADE DE CIÊNCIAS DA UNIVERSIDADE DE LISBOA
Dep. Engenharia Geográfica, Geofísica e Energia
Jorge F. Zeferino (Author)
FACULDADE DE CIÊNCIAS DA UNIVERSIDADE DE LISBOA
Ana S. Viana (Author)
FACULDADE DE CIÊNCIAS DA UNIVERSIDADE DE LISBOA
Upul Wijayantha (Author)
Cranfield Univeristy
Killian Lobato (Author)
FACULDADE DE CIÊNCIAS DA UNIVERSIDADE DE LISBOA
Jorge P. Correia (Author)
FACULDADE DE CIÊNCIAS DA UNIVERSIDADE DE LISBOA
Resumo
Lithium-ion batteries are, nowadays, the energy storage system with the most widespread use but, at this moment, there are insufficient lithium resources, consequently causing an unbalanced demand for this metal [1]. In terms of availability of raw material resources, sodium-ion batteries appear as a promising alternative. This change implies the design of new cathode materials capable of accommodating a larger ion [2]. The cathodic structure must be chemically stable and extremely light [3] to compensate the mass of the storage unit increase, imparted by the lithium replacement by sodium. An electronically conducting polymer with pseudocationic doping may fulfil these requirements.\\\\nIn this work poly(3,4-ethylenedioxythiophene) doped with poly(styrene-4-sulfonate) (PEDOT:PSS) films were galvanostatically synthesized at 0ºC for different time intervals (10 s – 80 s) on platinum electrodes from aqueous solutions containing the monomer and the polyanion. A strategy was followed to measure the optical properties and thickness variation felt as a function of the potential, during its redox conversion. Thus, films synthesized with different growth charges in aqueous medium, were characterized at room temperature in organic medium containing NaClO4 by cyclic voltammetry, with simultaneous recording of ellipsometric parameters. The plotting of psi vs. delta of the different films at selected potential values, allowed to simulate the effect of the growth of the films on the dielectric constants at different degrees of doping, as a function of their thickness. The optical constants obtained allow to assess the polymer properties imparted by the low temperature synthesis, as well as the swelling/shrinking behaviour due to the pseudocationic character of the doping process.\\\\n
Data de Publicação
2022-05
Instituição
FACULDADE DE CIÊNCIAS DA UNIVERSIDADE DE LISBOA
Evento
The 9th International Conference on Spectroscopic Ellipsometry
Identificadores da Publicação
Local
Beijing, China
Keywords
Sodium-ion batteries
PEDOT:PSS
in-situ Ellipsometry