Synthesis of Co3O4/WO3 Nanoheterojunction Photocatalyst for the Decomposition of Organic Pollutants Under Visible Light Irradiation

A highly efficient and visible light (lambda a parts per thousand yen 420 nm) responsive nanocomposite photocatalyst Co3O4/WO3 was developed by dispersing p-type semiconductor Co3O4 on the surface of n-type semiconductor WO3. The heterojunction Co3O4/WO3 demonstrated higher photocatalytic activity than WO3, Co3O4 and TiO2 nanoparticles for the complete decomposition of 2-propanol in gas phase and phenol in aqueous phase and evolution of CO2 under visible light irradiation. The highest photocatalytic efficiency of the composite Co3O4/WO3 was observed when calcined at 300 A degrees C for 2 h with 4.91 mol% Co3O4/WO3. The enhanced photocatalytic efficiency of the heterojunction was discussed based on the unique relative energy band positions and profound absorption of visible light by the semiconductors.