Iridescent stand-alone TiO2 films crystallized from aqueous solutions.
Stand-alone TiO2 films were prepared from aqueous solutions. Anatase TiO2 was crystallized on polypropylene substrates by the reaction of ammonium hexafluorotitanate and boric acid. Solid films were formed on the substrates after about 90 min. The films were then easily peeled off from the substrates to be stand-alone films. They had a rainbow coloring due to the iridescence of visible light. XRD analysis revealed that the films consisted of single-phase anatase TiO2 crystals. The crystals elongated along the c-axis to increase diffraction intensity from (004) planes and crystallite size perpendicular to (004) planes compared to those of (101) planes. The iridescent stand-alone TiO2 films were unconstrained by substrates and can therefore be pasted on the desired substrates, such as silicon, papers, meshes, and so forth.
National Institute of Advanced Industrial Science and Technology, 2266-98 Anagahora, Shimoshidami, Moriyama-ku, Nagoya 463-8560, Japan.
Yoshitake
Y
Masuda
Kazumi
K
Kato