“…Further cycling yields porous films up to 3 template layers thick with a 3D 30 honeycomb internal structure. Upon characterisation with XRay diffraction, Raman spectroscopy, SEM, voltammetry, and reflectivity measurements, the films are found to be amorphous, to have structural dimensions faithful to that of the template, several electroactive redox states and reflectivity 35 spectra significantly different from that of non-structured films. Such films should find applications in biology (IrOx is conducting, non reactive and biocompatible) but particularly optics because their optical density can be electrochemically controlled and the cavity diameters correspond to UV-visible 40 wavelengths.…”