Free-Standing, Water-Resistant, and Conductivity-Enhanced PEDOT:PSS Films from In Situ Polymerization of 3-Hydroxymethyl-3-Methyl-Oxetane
Sara M. Jorge,
Luís F. Santos,
Maria João Ferreira,
Carolina Marto-Costa,
Ana Paula Serro,
Adelino M. Galvão,
Jorge Morgado,
Ana Charas
Affiliations
Sara M. Jorge
Instituto de Telecomunicações, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
Luís F. Santos
Centro de Química Estrutural, Departamento de Engenharia Química, Institute of Molecular Sciences, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
Maria João Ferreira
Centro de Química Estrutural, Departamento de Engenharia Química, Institute of Molecular Sciences, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
Carolina Marto-Costa
Centro de Química Estrutural, Departamento de Engenharia Química, Institute of Molecular Sciences, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
Ana Paula Serro
Centro de Química Estrutural, Departamento de Engenharia Química, Institute of Molecular Sciences, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
Adelino M. Galvão
Centro de Química Estrutural, Departamento de Engenharia Química, Institute of Molecular Sciences, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
Jorge Morgado
Instituto de Telecomunicações, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
Ana Charas
Instituto de Telecomunicações, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
Free-standing films based on conducting polymers, such as poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS), offer many benefits over traditional metal electrodes for applications in flexible electronics. However, to ensure structural integrity when contacting aqueous environments and high levels of electrical conductivity, solution-processed polymers require additives that act as crosslinking agents and conductivity enhancers. In this work, a new approach is presented to fabricate water-resistant free-standing films of PEDOT:PSS and simultaneously increase their conductivity, using an oxetane compound as an additive. It is shown that at moderate temperatures, oxetane polymerizes within the PEDOT:PSS acidic medium, forming hydroxymethyl-substituted polyether compounds that form a network upon crosslinking with PSS. The polymer composite films show self-sustainability, structural stability in aqueous environments, and enhanced conductivity. Finally, the potential of the free-standing films as health-monitoring electrodes, specifically for human electrocardiography, is explored.
