Investigation of high-temperature phase transformation in one-dimensional Ta2O5 nanorods

The thermochromic phase transformations that occur in one-dimensional Ta2O5 nanorods were analysed at elevated temperatures ranging from 300 to 750 K. X-ray photoemission spectroscopy data revealed not only the electronic structures and chemical properties of the one-dimensional Ta2O5 nanorods, but also their stoichiometric Ta and O compositions. High-temperature X-ray diffraction data revealed complex and polymorphic thermochromic phase transformations of the alpha(1 0 11), alpha(200), alpha(2 0 10), beta(3 11 1) and beta(2 21 1) lattice planes in the one-dimensional Ta2O5 nanorods, which incorporate beta to alpha (beta-alpha), beta to beta (beta-beta), alpha to alpha (alpha-alpha) and alpha to beta (alpha-beta) phase transitions. The thermochromic phase transformations between alpha- and beta-phase crystals can be explained by a shift in 2 theta and expansion of the d spacing of the lattice planes.