FIG. 1 is a scanning electron micsrograph of Nippon Oil titania nanotube taken with a scanning electron microscope.
Nippon Oil Corporation (Tokyo, JP) inventors Keisuke; Nakayama, Takaya Kubo Yoshinori; Nishikitani and Hideki Masuda disclose a new nanofabrication method provides a nanotube-shaped titania which is uniform in structure and excellent in commercial productivity and has a sufficient aspect ratio in U.S. Patent Application 20100009001. A nanotube-shaped titania having an aspect ratio of 6 or greater can be produced by anodizing a titanium metal or an alloy containing mainly titanium in an electrolyte solution containing a halogen atom-containing ion, such as a perchloric acid aqueous solution.
FIG. 2 is a photograph of the Nippon Oil titania nanotube taken with a transmission electron microscope.
FIG. 2 is a photograph of the Nippon Oil titania nanotube taken with a transmission electron microscope.
The nanotube-shaped titania has a remarkably large in specific surface area and highly efficient in the propagation of electrons, holes, phonons, or complexes thereof due to its shape, compared with spherical titania. Therefore, when the nanotube-shaped titania is used as an ultraviolet absorber, a masking agent, an adsorbent, or a photoactive catalyst in particular, significant improvements in the working effects thereof can be expected, compared with the prior art.
When the nanotube-shaped titania is used as a catalyst support, it may be generally used, loading thereon a metal such as platinum, nickel, or silver. Alternatively, the nanotube-shaped titania exhibits the n-type semiconductor characteristics and thus can be used as a material with rectification properties such as a transistor by forming a p-type nanowire or nanotube with excellent electron transfer characteristics and allowing the contact point of these two different nano-structures to function as a pn junction.
FIG. 3 is a photograph of the Nippon Oil titania nanotube after being heated, taken with a transmission electron microscope.
