Abstract:Monoclinic BiPO₄ with rod-like shape was prepared via a CTAB-assisted hydrothermal route. MnO_x nanoparticles were loaded on the surfaces of BiPO₄ rods by a photo-deposition process to form MnO_x/BiPO₄ heterojunctions. The as-prepared samples were characterized by XRD, SEM, TEM, XPS, FL, and UV-Vis diffuse reflectance measurements. The results showed that MnO_x nanoparticles were strongly anchored to the surfaces of BiPO₄ rods when the mole ratio of Mn to Bi was controlled at a low level, forming MnO_x/BiPO₄ heterojunctions with effective and sound interfaces. The MnO_x/BiPO₄ heterojunctions exhibited higher photoactivity than pristine BiPO₄ for photodegradation of methyl blue under UV irradiation, which could be attributed to the efficient charge transfer at the heterojunction interfaces. The higher light absorption ability of MnO_x/BiPO₄ in the range of 300-420 nm compared with pristine BiPO₄ was also responsible for the enhanced photocatalytic activities of MnO_x/BiPO₄ heterojunctions.

Key words: BiPO₄; photocatalysis; hydrothermal method; MnO_x; heterojunction; photodeposition