Solvothermal synthesis and photocatalytic activity of Al-doped BiOBr microspheres

A series of Al-doped BiOBr microspheres with different Al contents were synthesized via a facile solvothermal method. The as-prepared samples were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), energy dispersive spectrometry(EDS), X-ray photoelectron spectroscopy(XPS), N2 adsorption-desorption and UV-visible diffuse reflectance spectroscopy(UV-vis DRS). The photocatalytic activity was evaluated by the photocatalytic degradation of methyl orange in an aqueous solution under visible light irradiation. The results revealed that Al doping could greatly improve photocatalytic performance of BiOBr and different Al contents resulted in different photocatalytic activities. The highest activity was achieved by 4 at%Al-BiOBr. The enhanced photocatalytic activity was attributed to efficient separation of photogenerated electron-hole pairs and large BET surface area.