Imaging of Hydrophilicity and its Inhomogeneity on a Titanium Dioxide Film Exposed to Ultraviolet Irradiation Using a Newly Developed Near-Infrared Camera

Abstract

This study has investigated hydrophilicity changes and their inhomogeneity of TiO2 films on Pyrex glasses by near-infrared (NIR) spectral imaging. Near-infrared spectra of TiO2 films in the 9000-4000 cm(-1) region were measured using a newly developed NIR camera named Compovision. A band in the 5400-4800 cm(-1) region, which is assigned to a combination (ν2 + ν3) mode of bending (ν2) and antisymmetric stretching (ν3) modes of the H2O molecule, was clearly identified and its intensity increased with time in the air. It is interesting that the increased rate rose with ultraviolet (UV) light irradiation (300-400 nm, 1 mW cm(-2)) compared to without UV light irradiation. This result suggested that the hydrophilicity of TiO2 was enhanced about twice upon the UV light irradiation. Moreover, the NIR images clarified spatial distributions of the hydrophilicity on the TiO2 surface with a significantly wide area (20 × 40 mm) and a high speed (within 5 s for one image). This rapid imaging system enabled us to detect the hydrophilicity change during only 1 min. The potential of this camera is quite superior, not only for basic research, but also for diverse industrial applications.

Noninvasive, high‐speed, near‐infrared imaging of the biomolecular distribution and molecular mechanism of embryonic development in fertilized fish eggs

“…In this study, a microscope NIR imaging system with a hyperspectral camera was used . Figure shows a schematic view of the microscopic NIR imaging system used.…”

“…This presents a really serious problem for biological samples. However, recently, Sumitomo Electric Industries Ltd., in collaboration with our group, developed an ultra‐high‐speed NIR imaging system based on a novel concept . This system was originally designed with a wide‐area NIR imaging device to obtain high‐speed and high‐quality images, but it can be also used for micro‐NIR imaging.…”