Preparation of silica and titania structured films by spray deposition

Abstract

Morphology control of the films is one of the important issues in recent years because this has resulted in materials with unusual properties and broadened their application range beyond the traditional use as catalysts and materials for the electronic devices. Macroporous titania film was synthesized using polystyrene latex as a template by spray deposition system at 150℃ and photocatalytic property was evaluated by measuring the degradation ratio of methylene blue under irradiation of UV lamp. Macroporous titania film showed higher degradation ratio of methylene blue than nonporous titania film. This result was caused by the increase of the surface area in titania film. Even though many kinds of well-established methods exist for the production of porous titania film, spray deposition system is promising alternative method because it is simple, cheap to operate, and environmental friendly with high quality and properties. Fabrication of folded shape structured $SiO_2$ films using oyster shell by spray deposition demonstrated a new strategy for the morphology control of the ceramic films. A new form of $SiO_2$ film with folded shape was generated by using phenomenological structural differences between chalky layer and folia layer in oyster shell induced from organic matrices. The main reason for $SiO_2$ film with folded shape is the differences in mechanical properties such as elastic modulus and strain between chalky and folia layer. This method might be applied to solar cell and electrical devices which requires specific folded or patterned structure.