Controllable hydrothermal synthesis of BiOCl nanoplates with high exposed {001} facets

Square-like bismuth oxychloride (BiOCl) nanoplates with high exposed {001} facets were successfully synthesized through a facile hydrothermal process in the presence of sodium citrate. Citric anions reduce BiOCl nanoplate size and lead to high intensity ratio of (001)–(102) by selectively absorbing on the {001} facets of BiOCl nanoparticles or nanoplates. Size of BiOCl nanoplates decrease to about 200 nm when 1.5 mmol sodium citrate was added. Thickness of BiOCl nanoplates also decreases from 100 nm to about 45 nm with increasing sodium citrate amounts. Diffraction peak intensity ratio of (001)–(102) of BiOCl nanopaltes is up to 0.93 with the adding of 1.5 mmol sodium citrate. As-obtained BiOCl nanoplates show a higher photocatalytic activity for degrading methyl orange (MO) than that prepared without sodium citrate under simulated sunlight irradiation.