High room-temperature photoluminescence of one-dimensional Ta205 nanorod arrays

摘要

In this study we analyzed the structural and electronic properties of a new morphological form,one-dimensional (1D) Ta_2O_5nanorod arrays, which were synthesized by hot filament metalvapor deposition. Field-emission scanning electron microscopy (FESEM) showed the 1D Ta-2O_5nanorods to be arranged in a large-area high-density array about 50 nm wide and approximately550 nm long. X-ray photoemission spectroscopy (XPS) revealed not only the electronicstructures and chemical properties of the 1D Ta_2O_5nanorods but also their stoichiometric Taand O compositions. Photoluminescence (PL) spectra showed intensive green-light,yellow-light and red-light emissions at room temperature. These emissions simultaneouslyemerged from the trap levels of oxygen vacancies within the Ta_2O_5bandgap. The emissionresults strongly indicate that the 1D Ta-2O_5nanorods are good room-temperature visible-lightemitters.