Preparation of Niobium(V) Oxide with Controlled Dispersity and Morphology

The effect of the annealing temperature and the chemical history of the precipitate on the morphology and phase composition of Nb 2 O 5 powder was investigated. The precipitate Nb 2 O 5 · n H 2 O and gel-like niobium citrate were obtained by solution methods. The synthesis of niobium oxide was conducted at temperatures 600, 1000, and 1200°C. The products of synthesis were analyzed by means of x-ray diffraction, scanning electron microscopy, x-ray microscopy, and differential thermal and thermogravimetric analysis. The annealing of niobium citrate at 600°C makes it possible to obtain niobium oxide particles with average size equal to about 70 nm, which is 4 – 6 times smaller than Nb 2 O 5 obtained from Nb 2 O 5 · n H 2 O precipitate.