Photochromic Performance of PLD grown MoO3Thin Films

Molybdenum trioxide (MoO3) thin films are made by Pulsed Laser Deposition (PLD) technique onto cleaned glass substrates at an oxygen partial pressure (PO2) of 100 m Torr by varying substrate temperature (Ts). The present study describes the variation in the growth of films and photochromic properties with respect to substrate temperature. XRD studies confirm unique α - orthorhombic layered structure for grown films and the intensity of prominent peaks increases with substrate temperature. SEM images discloses that the film surface constitutes uniformly spherical grains at lower substrate temperature (Ts = 100 ℃) and turns to needle like structure as substrate temperature reaches to 200 and 300 ℃. The films deposited at 400 ℃ gives nano-crystalline structure which shows stable and high photochromic efficiency. The studies also reveal that the presence of impurities or ions on the surface of the film and effects on the photochromic performance.