Fabrication of WO3@g-C3N4 with core@shell nanostructure for enhanced photocatalytic degradation activity under visible light

WO3@g-C3N4 composite photocatalysts with core@shell nanostructure were fabricated via a self-assembly method. A large heterojunction interfacial area of WO3@g-C3N4 can be provided in the nanoscale heterostructure. Furthermore, the electron mobility of the composite photocatalysts was improved with the introduction of WO3. These are favorable for increasing the separation efficiency of photoinduced electron-hole pairs and improving the photocatalytic efficiency of WO3@g-C3N4, which was confirmed by the measurements of photocurrent and electrochemical impedance spectroscopy. The results of the photocatalytic degradation of Rh B showed dramatic photocatalytic performance of this composite photocatalyst. The kinetic constant of Rh B degradation on the WO3@g-C3N4 was 0.95 h−1, which was 7.7-fold and 3.5-fold higher than those on pure WO3 and g-C3N4 nanosheets, respectively. In addition, the stability of the composite photocatalyst was also satisfactory according to the result of the three-cycle experiment.