Effect of ZnSe doping on the photochromic and thermochromic properties of MoO3 thin films

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. The characteristic optical absorption band attributed to color center formation indicated an enhanced photochromic effect for MoO3 films doped with ZnSe 5 mol% relative to undoped MoO3 samples. In addition, the thermochromic effect was most pronounced for ZnSe 5 mol% samples annealed at 23–125 °C, and for undoped samples annealed at 125–225 °C. The chromogenic properties were essentially suppressed for MoO3 doped with ZnSe 10 mol%.