Fabrication and photoactivity of organic-inorganic systems based on titania nanotubes and PEDOT containing redox centres formed by different Prussian Blue analogues

Herein, the heterojunction composed of an inorganic substrate: ordered hydrogenated titania nanotubes (H-TiO_{2}NTs) and a deposited organic film: poly(3,4-ethylenedioxythiophene) (PEDOT) is reported. The conducting polymer is modified with different transition metal haxacyanoferrates (Mehcf), wherein as metal: copper, iron, cobalt and nickel are introduced. The presence of various metal centres provides characteristic redox activity and allows to investigate the impact of the particular Prussian Blue analogues onto the photoactivity of the p-n heterojunction. The formed composites were inspected by means of scanning electron microscopy, spectroscopic techniques, i.e. UV–Vis, Raman and Secondary Ion Mass spectrometry and using electrochemical methods. It is shown that electrochemical and photoelectrochemical performance of the so-fabricated materials is significantly affected by the nature of the redox species introduced into the PEDOT matrix.