Interface porosity in multilayered all‐conducting polymer electrodes

Multilayered films made with at least two different electroactive polymers, in which the least conducting one acts as a dielectric and separates the layers made with the other, behave as efficient electrodes for electrochemical supercapacitors. In this work, we present a simple strategy to develop improved multilayered electrodes with structured interfaces by enhancing the porosity of the dielectric. This has been achieved by growing sodium chloride crystals onto a conducting polymer layer and, after generation of all required layers using the layer‐by‐layer electrodeposition technique, salt crystals have been eliminated by water etching. Results from morphological and topographical studies on single‐layered poly(3,4‐ethylenedioxythiophene) (PEDOT), poly(N‐methylpyrrole) (PNMPy), and poly(3,4‐ethylenedioxythiophene‐co‐N‐methylpyrrole) (COP), as well as electrochemical investigations on bi‐layered films with enhanced porosity at the interface between the two layers, have been used to design new four‐layered electrodes. These consist in two layers of PEDOT separated by two layers of nanosegregated COP with a porous interface in the middle. Although the properties of the new four‐layered electrodes improve due to the porous interface, the highest specific capacitance corresponds to the two‐layered electrode in which two PEDOT layers are separated by an ultra‐porous interface. POLYM. ENG. SCI., 59:1624–1635 2019. © 2019 Society of Plastics Engineers