Herein, we report the fabrication and characterization of a hierarchical TiO2 structure that exhibits reduced surface reflection. The hierarchical structure, which is a moth-eye-shaped array containing nanotubes, was fabricated by dry-etching a TiO2 nanotube layer, by using colloidal lithography. The fabricated structure shows a reduced reflectance, compared with that of non-patterned TiO2 nanotubes. This is because of the graded refractive index of the moth-eye pattern. Furthermore, we investigated the optical properties of gold-decorated moth-eye TiO2 nanotubes and found that the absorption, which was caused by the plasmonic resonance of gold nanostructures, was further enhanced by coupling with the light-trapping effect.
Bibliographical noteFunding Information:
National Research Foundation of Korea (NRF) (NRF-2013M3C1A3065045); Ministry of Science, ICT and Future Planning (CAMM-2014M3A6B3063712)
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All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics