The second feature (labelled β), observed on the backward scan, is a sharp negative peak that occurs at ca. -0.1 V. The shape of the peak, in terms of the absence of a diffusional tail, and sharp increase in intensity suggests a type of adsorption or surface process at the polarisable L|L interface. We attribute this feature to the interfacial adsorption of EDOT oligomers at the bare L|L interface. The EDOT oligomers are cationic in nature, as demonstrated vide infra, and upon adsorption are involved in an anion exchange process where the weakly coordinating organic soluble tetrakis(pentafluorophenyl)borate anions (TB -) anions are exchanged by aqueous sulfate anions (SO4 2-), see Fig. . This interpretation is supported by a previous X-ray photoelectron spectroscopy study where PEDOT thin films formed by interfacial electrosynthesis were found to be exclusively doped by SO4 2-, with no traces of TB - found. The electrostatic charge on the cationic EDOT oligomers is increasingly compensated by SO4 2-anions as the applied Δ o w 𝜙 is scanned more negative than the potential of zero charge (PZC), giving rise to the sharp negative peak (modelled vide infra). The magnitude of this peak rapidly increases until the 4 th cycle (Fig. ), after which the peak abruptly begins to decrease in magnitude and shift to a slightly more positive applied Δ o w 𝜙 with subsequent cycles (Figs.