A simple chemical method for deposition of electrochromic Prussian blue thin films

This paper is about a recently developed new chemical method for deposition of Prussian blue thin films. The films are easily prepared by successive immersion of the substrates into an acidic aqueous solution of Fe₂(SO₄)₃ and K₄[Fe(CN)₆]. It is calculated of the results from AFM analysis that the growth in the film thickness by one immersion cycle corresponds to an average increase of 6 nm. The characterization of the films with X-ray diffraction, SEM-EDS analysis and FTIR spectroscopy shows that the deposited material is amorphous hydrated Fe₄[Fe(CN)₆]₃. The electrochromic properties are characterized by cyclic voltammetry and VIS spectrophotometry. The PB thin films exhibit stability and excellent reversibility, which make these films favorable for electrochromic devices.