A novel construction of Z-scheme CuO/g-C3N4 heterojunction for visible-light-driven photocatalysis in natural seawater

In the present study a simple and convenient solution route to grow submicron-sized CuO structures onto the surface of g-C3N4 was demonstrated and the upgraded visible-light-driven photocatalytic activity of the as-prepared composite was revealed. The buildup of CuO(4.4 wt%.)/g-C3N4 p-n heterojunction was successfully accomplished via two-step ammonia-evaporation-induced synthetic approach. The resulting inorganic/organic composite was characterized by X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, thermogravimetry, ultraviolet-visible diffuse reflectance spectroscopy and photoluminescence spectroscopy to examine its phase structure, valence state, microstructural, thermal and optical properties. Its photocatalytic efficiency was tested using Malachite Green photodegradation in natural seawater and the results indicated that CuO/g-C3N4 is much more active than the individual components in the photodegradation of MG. A plausible photocatalytic mechanism was also proposed.