Morphology-controllable synthesis of BiOBr architectures and their visible light photocatalytic activities

A series of hierarchical BiOBr architectures were successfully prepared via a simple solvothermal method. The as-prepared samples were characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2-sorption and UV–Vis diffuse reflectance spectroscopy. The results showed that the morphologies of BiOBr architectures could be controlled by adjusting the addition amount of acetic acid (HAc) without changing their crystallinities, whose reason was discussed. The photocatalytic activities of the prepared BiOBr architectures were evaluated by degradation of methyl orange (MO) under visible light irradiation. It was found that the as-prepared BiOBr architectures exhibited morphology-dependent photocatalytic activities, among which the photodegradation efficiency of the sample prepared with 5 mL of HAc was as high as 94.3% within 100 min visible light irradiation. The enhanced photocatalytic activity was attributed to strong visible light adsorption, high BET surface area and high separation efficiency of the photogenerated electron-hole pairs.