Hydrothermal synthesis of bamboo-shaped nanosheet KNb₃O₈ with enhanced photocatalytic activity

A new type of bamboo-shaped KNb₃O₈ nanosheet was synthesized by using a two-step hydrothermal method. In particular, an effect of potassium content on the phase formation of KNb₃O₈ in the second-step hydrothermal process at pH = 5-6 was investigated. Specific surface area, structural properties and optical characteristics of the as-synthesized samples were investigated by using Brunauer-Emmett-Teller measurement, X-ray diffraction analysis, scanning electron microscopy, transmission electron microscopy and UV-visible diffuse reflectance. Furthermore, the photocatalytic degradation performances of the bamboo-shaped KNb₃O₈ nanosheet and a rod-like KNb₃O₈ prepared by using molted salt method were also investigated and compared in terms of degradation of Rhodamine B, and the results indicated that the bamboo-shaped KNb₃O₈ nanosheet had a higher photocatalytic activity.