Three isomeric ionene polymers containing 1,4-diazabicyclo[2.2.2]octane (DABCO) and N,N’-(x-phenylene)dibenzamide (x= ortho- / meta- / para-) linkages have been used as dopant agents to produce n-doped poly(3,4-ethylenedioxythiophene) (PEDOT) electrodes by reducing already dedoped conducting polymer (CP) films. This work focuses on the influence of the ionene topology in both the properties of n-doped PEDOT:ionene electrodes and the success of the in situ thermal gelation of the ionene inside the CP matrix. The highest doping level is reached for the para-isomeric ionene-containing electrode, even though the content of ortho- and meta-topomers into the corresponding n-doped PEDOT:ionene electrodes is greater. Thus, many of the incorporated ionene units are not directly interacting with CP chains and, therefore, do not play an active role as n-dopant agent but they are crucial for the in situ formation of ionene hydrogels. The effect of the ionene topology is practically inexistent in properties like the specific capacitance and wettability of PEDOT:ionene films, and it is small but non-negligible in the electrochemical and thermal stability. In contrast, the surface morphology, topography, and distribution of dopant molecules significantly depend on the ionene topology. In situ thermal gelation was successful in PEDOT films n-doped with the ortho- and para-topomers, even though this assembly process was much faster for the former than for the latter. The gelation considerably improved the mechanical response of electropolymerized PEDOT film, which was practically non-existent before it. Molecular dynamics simulations prove that the strength and abundance of PEDOT···ionene specific interactions (i.e. ¿-¿ stacking, N–H···S hydrogen bonds and both N+···O and N+···S interactions) are higher for the meta-isomeric ionene, for which the in situ gelation was not achieved, than for the ortho- and para-ones.

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