Recognizing conductive islands in polymeric redox surfaces using electrochemical-coupled vibrational spectromicroscopy

Abstract

We introduce a set up by coupling multiplex FTIR microscopy to electrochemistry through a home-made spectroelectrochemical cell to observe real time changes in the electronic states of polymeric islands by monitoring the oxidation states of polyaniline (PANI). The resultant technique, called electrochemical-coupled vibrational spectromicroscopy (EVSM), enables the measurement of structural changes in the conductive islands of PANI with the spatial resolution as high as 2.5 μm. Unique 2D and 3D chemical maps obtained by the integration of the spectral bands in the subtractively normalized interfacial infrared (SNIFTIR) spectra reveal electrochemical heterogeneity, showing promising topological properties control for conducting polymer-based electronic devices.