One-step template-free synthesis of BaSb2O6 micro-flowers and their associated photocatalytic activity

Abstract

The rose-flower-like BaSb₂O₆ (R-BaSb₂O₆) and marigold-flower-like BaSb₂O₆ (M-BaSb₂O₆) have been successfully prepared by a simple hydrothermal method avoiding high temperature, templates, catalysts, surfactants, or organic solvents. Their structures and morphologies have been investigated by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy and selected-area electron diffraction. Ba/Sb molar ratio and pH values in the precursor play significant roles in building two kinds of flower-like BaSb₂O₆. Time dependent experiments reveal the possible formation mechanisms of the BaSb₂O₆ microstructures. When used as a photocatalyst, the M-BaSb₂O₆ exhibits the best photocatalytic activity among R-BaSb₂O₆, M-BaSb₂O₆ and BaSb₂O₆ synthesized by solid state reaction. The morphology of M-BaSb₂O₆ results in the large BET specific surface area and unique light propagation mode, which greatly improve the interaction among photons, organic compounds and photocatalyst, and thus enhance photocatalytic activity. The photocatalytic stability experiments demonstrate the sufficient stability of M-BaSb₂O₆ during the photocatalytic process.