Hydrothermal synthesis of potassium titanate nanotubes doped with magnesium, nickel, and aluminum

Abstract

Study of the phase formation in the systems TiO₂‒MO(M₂O₃)‒KOH‒H₂O (M = Mg, Ni, Al) from crystalline and coprecipitated X-ray-amorphous mixtures demonstrated that doped potassium titanate nanotubes can be obtained in a hydrothermal treatment of coprecipitated hydroxides in the temperature range 170‒220°C. The average outer diameter of the thus synthesized nanotubes strongly depends on the element being introduced and is 5 to 10 nm. The nanotubes have a large specific surface area (200‒300 m2 g‒1) and are stable up to a temperature of 500°C, above which they decompose to give potassium hexatitanate. The nanotubes can be used as sorbents, photocatalysts, and components of composite materials for frictional and construction purposes.