Design of a highly photocatalytically active ZnO/CuWO4 nanocomposite

Here we report the synthesis, photocatalytic activity and mechanistic study of a novel charge separation heterostructure (HTS). A ZnO/CuWO4 HTS material is reported for the first time. The nanocomposite (NC) consist of CuWO4 nanoparticles (ca. 200-400nm) decorated with ZnO nanorods (ca. 30nm, 100nm length) and is shown to be a highly active photocatalyst for the decomposition of model contaminants including methyl orange (MO) and terephthalic acid (TPA). The ZnO/CuWO4 interface is shown to be key in controlling the enhanced activity of the composite material. Transient absorption (TA) spectroscopy studies demonstrate that photoinduced charge transfer across the ZnO/CuWO4 interface increases electron-hole lifetimes by 3 orders of magnitude, from <20μs in ZnO to 30ms in the ZnO/CuWO4 NC sample. Our findings show that through interface design efficient HTS materials can be prepared for a wide range of photocatalytic applications.