Preparation and characterization of a new copper antimony oxide, Cu 9Sb 4O 19

Abstract

The new copper antimony oxide, Cu 9Sb 4O 19, was prepared by solid-state reaction between CuO and CuSb 2O 6 in a 3.5:1 mole ratio at 1000–1100°C and 10 kbar using a piston cylinder-type high-pressure apparatus. It is certain that the decomposition of Cu(II) to Cu(I) in mixtures of CuO and CuSb 2O 6 hinders the formation of Cu 9Sb 4O 19 at temperatures ≥1200°C. The Cu 9Sb 4O 19 powder pattern could be indexed on the basis of a body-centered cubic unit cell with a 0 = 9.620Å. The Cu 9Sb 4O 19 was found to decompose to Cu 4SbO 4.5 + CuSb 2O 6 with evolution of oxygen at 950–990°C in air by TG and DTA. The Cu 2 p XPS showed the more ionic character of the copper ions in Cu 9Sb 4O 19 than in CuSb 2O 6. Furthermore, the asymmetric Sb 3d 3 2 spectrum for Cu 9Sb 4O 19 suggested two types of Sb(V) with different chemical environments.