Hierarchical structured bismuth oxychlorides: self-assembly from nanoplates to nanoflowers via a solvothermal route and their photocatalytic properties

A simple solvothermal route was explored to prepare hierarchical, nanostructured flower-like bismuth oxychlorides (BiOCl) by employing pyridine as the solvent. The volume ratios of distilled water to pyridine play an important role in the assembly of the BiOCl nanostructure from nanoplates to nanoflowers. The as-prepared BiOCl nanoflowers were characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, and nitrogen sorption. The resulting BiOCl nanoflowers with high specific surface area were phase-pure and self-assembled from thin nanoplates during the reaction process. In addition, the photocatalytic properties of the as-prepared samples were further investigated by photocatalytic decomposition of methyl orange (MO) dye, and it was found that the BiOCl nanoflowers showed a higher photocatalytic activity than that of TiO2 (Degussa, P25) under modeling sunlight.