Optical property of atomically thin titanium-oxide nanosheet for ultraviolet filtration

Two-dimensional (2D) materials with infinite planar dimensions have attracted much attention due to their unique crystal structure and three-dimensional anisotropy. A 2D titanium-oxide nanosheet was synthesized in this study, and its optical property in terms of being a candidate material for an ultraviolet (UV)-protecting material was investigated. The titanium-oxide nanosheet was produced to be about 1 nm-thick by the chemical exfoliation of single crystalline potassium intercalated titanium oxide. Its crystal structure and chemical composition were investigated with X-ray diffraction, electron microscope, and thermogravimetric analysis. Sheet films with various thickness were fabricated using layer-by-layer coating with the titanium-oxide nanosheet, and their optical properties were investigated as a function of film thickness. They efficiently protected from UV-rays, and their UV-protection was much higher than that of common UV-protectors at similar film thickness.