Fabrication of nitrogen defect mediated direct Z scheme g-CN/BiWO hybrid with enhanced photocatalytic properties.

A direct Z scheme g-CN/BiWO heterojunctions with enhanced photocatalytic performances were successfully prepared through nitrogen defect mediated method. HRTEM analyses illustrate BiWO nanoparticles are closely bonded with the g-CN-0.05 nanosheets to form the g-CN-0.05/BiWO heterogeneous structures. An outstanding visible light absorption ability is shown in the g-CN-0.05/BiWO hybrid, which combines both the light absorption advantages of g-CN-0.05 and BiWO together. In comparison with other photocatalysts the nitrogen defect mediated g-CN-0.05/BiWO hybrid shows the best photocatalytic properties, whose degradation efficiency can reach 83%. PL results indicate that an obvious larger amount of ·OH radical is produced on the g-CN-0.05/BiWO surface in the photocatalytic process. In the nitrogen defect mediated g-CN-0.05/BiWO the binding energies of C and N shift positively to the larger binding energy and the Bi, W and O elements shift negatively compared with that of the pristine g-CN-0.05 and BiWO. The MS results show the g-CN-0.05 has a more negative E than that of BiWO. All the experimental results support the direct Z scheme charge transfer mechanism proposed in the g-CN-0.05/BiWO photocatalyst. The developing of direct Z scheme g-CN-0.05/BiWO hybrid with excellent photocatalytic performance through defect mediated method shows great potential for more photocatalytic fields.