Optical properties of titanium dioxide nanotube arrays

摘要: We present experimental measurements and a theoretical analysis of the near UV to NIR optical properties free standing titania nanotube arrays. An improved understanding physics this type nanostructure is important several next generation solar energy conversion technologies. measured transmission, reflection, absorption electromagnetic spectrum from 300 nm 1000 nm (UV NIR) total, specular, diffuse reflection transmission using both single point detection an integrating sphere spectrometer. find that but not light through array well-explained by classic geometric optics effective medium model taking into account conical geometry nanotubes. For wavelengths shorter than ∼500 nm, we surprising result coefficient for incident on open side greater closed “floor” array. consider models based eikonal approximation, photonic crystal band theory, statistical treatment scattering explain observed data. attribute fact with 500 nm more highly reflected tube as being due disorder inside