Photochromism and thermochromism of MoO3 thin films doped with ZnSe

The photochromic and thermochromic properties of molybdenum oxide (MoO3) thin films doped with zinc selenide (ZnSe) were studied. The films were deposited on glass substrates by thermal evaporation of MoO3-ZnSe powder mixtures. EDS measurements confirmed the incorporation of ZnSe in the MoO3 matrix while MicroRaman spectra of the samples showed structural changes by increasing ZnSe. MoO3 films doped with 5 mol% ZnSe presented an enhancement in the photochromic effect compared to the undoped MoO3 samples. The thermochromic effect was most pronounced for 5 mol% ZnSe samples annealed at 23-125 °C, and for undoped samples annealed at 125-225 °C. The MoO3 films doped with 10 mol% showed neither photochromic nor thermochromic effect.