Synthesis of a New Photochromic ZrO2 Precursor for Preparation of Functional Thin Films
A new photochromic ZrO2 precursor solution was prepared using zirconium tetra-n-butoxide, 4-(phenylazo)benzoic acid and ethyleneglycol monomethylether. The ZrO2 precursor solution was irradiated with ultraviolet light (UV) at room temperature. After that, UV-irradiated precursor solution was irradiated with visible light (Vis) at room temperature. UV-Vis spectra were measured before irradiation, after UV irradiation and Vis irradiation. Changes of UV-Vis spectra indicated that the new ZrO2 precursor including 4-(phenylazo)benzoic acid shows photochromism. The phenomena have synchronized with reversible photoisomerization of 4-(phenylazo)benzoic acid in the precursor. In addition, the difference of peak position originated from Zr-O CT transition between before UV irradiation and after UV irradiation increased with increasing the concentration of 4-(phenylazo)benzoic acid. Furthermore, the optimized structure of the new ZrO2 precursor was derived by density functional theory (DFT) calculation.
Keiichi Katayama, Kazumi Kato, Tadashi Takenaka, Masasuke Takata and Kazuo Shinozaki
K. Nishizawa et al., "Synthesis of a New Photochromic ZrO2 Precursor for Preparation of Functional Thin Films ", Key Engineering Materials, Vol. 320, pp. 175-178, 2006