Electrochromic properties of manganese oxide (MnOx) thin films made by electron beam deposition

Electrochromic MnOx thin films are prepared by using an electron beam technique followed by annealing post-treatment. Electrochromic properties of the films are studied in three different solutions: 1M LiClO4 in propylene carbonate, KOH (pH = 10.5), and natrium borate (pH = 9.2). The transmittance spectra of the coloured films combined with their cyclic voltammetry curves show that the enhancement of the electrochromic behaviour of these films can be attributed to the insertion (or extraction) of the OH- anions into (or from) the MnOx films. The best electrochromic efficiency of the films is obtained in the borate electrolyte.