Preparation and proton conductivity of monodisperse nanocrystals of pyrochlore-type antimonic acid and its niobium-substituted materials

Abstract The well-defined monodisperse nanocrystals of pyrochlore-type antimonic acid, HSbO 3 · n H 2 O ( n  = 0.5), and its niobium-substituted materials, HSb 1− x Nb x O 3 · n H 2 O (0 ≤  x  ≤ 0.09, n  = 0.5), were successfully prepared by solution processing using the direct reaction of an aqueous H 2 O 2 solution with antimony and niobium alkoxides, Sb(O- iso -C 3 H 7 ) 3 and Nb(O- iso -C 3 H 7 ) 5 . It was found that the crystal sizes of these materials can be controlled from 35 to 50 nm with intervals of a few nanometers by changing the initial Sb(O- iso -C 3 H 7 ) 3 concentration. The proton conductivity of the materials is discussed in relation to their structural properties.