We evidence field-electron emission (FE) studies on the large-area array of one-dimensional (1D) brookite (b) TiO 2 nanorods. The pure 1D b-TiO 2 nanorods of 10 nm width and 760 nm long were synthesized on Si substrate utilizing hot-filament metal vapor deposition technique. X-ray diffraction (XRD) and transmission electron microscopy (TEM) analysis evidenced the b-TiO 2 nanorods to be composed of orthorhombic crystals in brookite (b) phase. X-ray photoemission spectroscopy (XPS) revealed the formation of pure stoichiometric (i.e. 1 : 1.98) 1D TiO 2 nanorods. The values of turn-on field, required to draw current density of 10 mA cm À2 , was observed 3.9 V mm À1 for pristine 1D b-TiO 2 nanorods emitters, which were found significantly lower than doped/undoped 1D TiO 2 nanostructures (i.e. nanotubes, nanowires, nanorods) based field emitters. The enhanced FE behavior of the TiO 2 /Si emitter can be attributed to modulation of electronic properties due to the high aspect ratio of vertically aligned TiO 2 nanorods. Furthermore, the orthodox emission situation of pristine TiO 2 /Si emitters exhibit good emission stability and reveal their potentials as promising FE material.

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Real-time surface differential reflectance spectroscopy in the visible range is used to study the optical response of silver nanoclusters, prepared by magnetron sputtering deposition, during cyclic treatments in different oxygen atmospheres and low-energy bias argon plasma. Changes in the reflectance show that the exposure to non-ionized (or partially ionized) oxygen causes a red-shift and damping (or complete vanishing) of the resonance, while bias plasma annealing induces the opposite effects, due to oxygen desorption and structural reshaping of the nanoclusters. These results open up new opportunities for developing plasmon-based devices with high tunability of the surface plasmon resonance (energy, width and amplitude) due to an interplay between morphological and chemical modifications of the nanoclusters.