Photochromic and hydrophilic vanadium oxide-molybdenum oxide composite thin films

Vanadium oxide-molybdenum oxide (VO-MO) composite thin films with a thickness of 500 nm were fabricated by thermal evaporation method on a quartz substrate with different compositions of vanadium oxide and molybdenum oxide (VO75% MO25%, VO50% MO50% and VO25% MO75%). The crystallite size in the prepared VO-MO thin films was found to be around 21-30 nm in size. The VO-MO films showed good crystalline nature (phase of vanadium oxide VO2 along with MoO3). The fabricated composite thin films showed photochromic properties when exposed to sunlight. The thin films possessed multicolorism under sunlight irradiation. The fabricated films showed good reversible property on bleaching. The hydrophilic nature of VO-MO composite thin films was also studied. The thin films were characterized by XRD, XPS and AFM. Transmission spectra of the thin films after sunlight irradiation confirmed that the prepared thin films have an excellent photochromic property with remarkable reversibility. Surface wettability property of the prepared VO-MO thin films was studied by using water contact angle measurements. Thin film with VO50% MO50% composition showed better photochromic and hydrophilic properties.

Automated summary

VO-MO composite thin films with different compositions of vanadium oxide and molybdenum oxide (VO75% MO25%, VO50% MO50% and VO25% MO75%) were fabricated by thermal evaporation method. The films exhibited photochromic properties and multicolorism under sunlight irradiation, and showed good reversibility on bleaching. The VO50% MO50% composition showed better photochromic and hydrophilic properties.