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Simple three-layer Fresnel equations combined with Maxwell-Garnett approximation were applied to study the IR plasmonic properties of indium-tin-oxide (ITO) nanorods. By treating the anisotropic nanorod layer as a layer with an effective dielectric constant, and using anisotropic effective medium theory, we were able to accurately predict the surface plasmon resonance behavior of ITO nanorods with different nanorod length, spacing, and tilt angle. This model allows a fast and computationally inexpensive calculation to predict the plasmonic properties of arrayed nanorods.

A multifunctional antireflective (AR) thin film is always a prerequisite for growing high-tech applications. Herein we proposed a surface modification technique to transform the hydrophilic behaviour of HfO 2 AR nanofilms into hydrophobic without influencing the nanostructure, morphology, refractive index (η) or AR efficacy of HfO 2 nanofilms. Our experimental results demonstrate that the fabricated HfO 2 AR nanofilms retain its AR efficiency after surface modification to <1% in the visible wavelength range (450-700 nm) on FTO and sapphire. HfO 2 AR nanofilms show hydrophilic behaviour before surface modification with a water contact angle (WCA) of 29° on FTO and 22° on sapphire. However, after surface treatment, they display hydrophobic nature θ w  > θ > 90° with a contact angle of (127°-130°). The experimental result demonstrates that the η of the thin layers fabricated at deposition angle 0°, 80°, and 88° before and after modification remains almost the same. HfO 2 AR nanofilms exhibit long term AR permanency as AR efficiency measured within a year practically displays the equivalent reflectance curves similar to as deposit AR thin films, i.e. <1% in the wavelength range of 450-700 nm. We proposed a cost-effective procedure to make hydrophilic AR films to show non-wetting behaviour for its long-term exposure in a moist, damp environment without affecting the refractive index of AR thin film.

Multifold Ag nanorods (AgNRs) have demonstrated great potentials in applications such as surface-enhanced Raman scattering technique due to their specially organized nanostructures. However, there is so far no systematic understanding of their localized surface plasmon resonance (LSPR) behaviors. This work comprehensively studied the plasmonic behaviors of AgNRs with 1, 2 and 3 folded arms. LSPR modes with charge oscillations resembling standing waves were excited in all nanostructures. As arm length increases, there were linear relationships between resonance wavelength and arm length, which applied to all LSPR modes studied. In addition, directly proportional relationships between the slopes of the linear functions and arm number were found for same order LSPR modes of AgNRs. For different modes of a specific AgNR, inversely proportional relationships between the slope and the resonance order N were discovered. These findings evidenced AgNR's standing wave type LSPR characteristics.

When heated in a rapid thermal processor at 350 °C in air, cobalt thin (50 nm thick) films were transformed into Co(3)O(4) nanorods in minutes. The nanorods are single-crystalline and are typically several hundred nanometers long and several tens of nanometers in diameter. They exhibited room-temperature photoluminescence in the visible range and good field emission properties, i.e. a low turn-on field of ∼2.8 V µm(-1) and good stability at high emission currents. This study provides a simple but rapid approach that is compatible with microtechnology and is capable of fabricating metal oxide nanorods at low substrate temperatures, on a large scale.