Iridescence of patterned carbon nanotube forests on flexible substrates: from darkest materials to colorful films.

In this study, we prepared carbon nanotube (CNT) forests exhibiting two types of optical properties: so-called "darkest materials" and films displaying iridescence phenomena. The darkest materials, comprising vertically aligned CNT (VA-CNT) forests, displayed extremely low reflections as a result of the rough surface and the trapping of light in the CNT forests. The lengths of the CNTs in the CNT forests had a strong influence on whether the light transmitted through the CNT forest or reflected from the substrate.

Two-dimensional metallic nanobowl array transferred onto thermoplastic substrates by microwave heating of carbon nanotubes.

The unique heating property of microwave irradiation on carbon nanotubes (CNTs) was applied in fabrication of a new architecture of two-dimensional metallic nanobowl array on a thermoplastic substrate. Vertically aligned CNT film was grown on a metal coated polystyrene (PS) submicron sphere array and then transferred onto a polycarbonate (PC) substrate by microwave heating. The back diffracted light spectra of this structure were measured and discrepancies between the spectra and that predicted from a diffraction relationship were studied.