Electrodes consisting of PEDOT modified by Prussian Blue analogues deposited onto titania nanotubes - their highly improved capacitance

In this work we present the outstanding energy storage of prepared inorganic-organic heterojunction where hydrogenated ordered titania nanotubes (H-TiO2NT) were modified by the hybrid made of poly(3,4-ethylenedioxythiophene) (pEDOT) and iron hexacyanoferrate centres (Fehcf, Prussian Blue). The material TiO2NT/pEDOT:Fechf was obtained electrochemically by means of: anodization, hydrogenation and finally, electropolymerization of EDOT in the presence of Fe(CN)63 −/4 − ions. Inorganic-organic hybrids were characterized using Raman spectroscopy and secondary ion mass spectrometry (SIMS). The morphology of obtained materials was inspected using scanning electron microscopy (SEM). Electrodes were tested using cyclic voltammetry and galvanostatic charge/discharge cycles in an aqueous electrolyte. The characterization of capacitance was studied by means of multiple (up to 10,000) charge/discharge cycles with the current density of 0.45 mA cm− 2. Electrode materials consisting of H-TiO2, pEDOT and Prussian Blue exhibited the highest capacitance of 26 mF cm− 2 even after 10,000 cycles. Thus, the capacitance of TiO2NT/pEDOT:Fehcf was c.a. 15 and 8 times higher than the capacitance registered for pure and hydrogenated TiO2, respectively.