Hexaniobate nanotubes with variable interlayer spacings

The novel hexaniobate nanotubes with variable interlayer spacings have been prepared via intercalating–exfoliating–rolling mechanism at the room temperature. The hexaniobate nanotubes are single crystalline with multiple walls. A few single-wall nanotubes have been observed also. The interlayer spacings of 0.83, 1.9, 2.2, 2.3, 2.4, 2.5, 2.8, 3.3 and 3.6 nm are, respectively, obtained by the intercalation of a series of primary alkylamines. The formation mechanism is discussed in detail and this method is applicable to other layered structure materials. These hexaniobate nanotubes are inorganic/organic composite and therefore represent a new class of tubular materials.