Confirmation that the bubble formation is indeed responsible for the rapid rupture of the film is provided in Fig. 2 where video stills capture the electrolysis process before and after the commencement of the reducing potential. It can be seen from Fig. 2 that a minor rip emerges in the film as the bubble of hydrogen is released. It must also be noted that there will be an increase in the local pH within the fibre mesh as the protons are reduced. This was confirmed through examining the peak position of quinoid functionalities on the surface of the anodised carbon fibre [18] and [19]. Such species are endogenous to carbon substrates and their population can be markedly increased through the use of electrochemical anodisation [18]. Crucially, the peak position is pH dependent and thus can serve as an indirect marker of local pH. In the present investigation, the carbon fibre was anodised as described previously and a calibration group detailing the response of the quinoid oxidation peak to varying pH covers the range pH 3 to pH 10. The response was found to be linear (E/V = − 0.069 pH + 0.428; N = 8; R2 = 0.994) although the gradient is larger than Nernstian predictions [18] and [19]. In order to assess the change in pH as a consequence of the electrolysis, the anodised carbon fibre was placed in the KCl electrolyte (adjusted to pH 3 in accordance with the previous study detailed in Fig. 1). Square wave voltammograms were recorded before and after the imposition of the electrolysis conditioning step and are detailed in Fig. 2. It can be seen that there is a distinct shift in the peak process and can be attributed to the increase in local pH. The peak returns to the pre conditioning potential shortly after the electrolysis has finished as the bulk solution returns the pH to the initial state