Study about an assembly of iron(III) hexacyanoferrate(II) and α-Fe2O3 as a secondary photocell: Part 1. Synthesis, characterization and photoelectrochemical properties of FTO/α-Fe2O3/KFe[Fe(CN)6]3 electrode system

This study addresses the synthesis and characterization of iron(III) hexacyanoferrate(II) (Prussian blue, PB) deposited on a semiconductor hematite electrode (α-Fe2O3). The formation of the Prussian blue/hematite interface was carried out by cyclic voltammetry. The modified electrode was morphologically characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM), structurally by x-ray diffraction (XRD), and photoelectrochemically by cyclic voltammetry under polychromatic illumination. The structure of the electrode system shows a cauliflower type morphology, with the typical PB structure. The electrochemical characterization indicates an increase of the currents of the low- and high-spin iron systems of PB when the system is illuminated, indicating that photogenerated charge carriers are involved.