Constructing Imidazole-Modified g-C3N4/SnO Heterojunction for Photodegradation

An effective strategy for significantly enhancing photocatalytic activity of composite materials is to construct heterojunctions. Herein, a series of imidazole-modified heterostructured g-C3N4/SnO (CNIS) Z-scheme photocatalysts were prepared by calcination methods, leading to superior photocatalytic performance than pure SnO and imidazole-modified g-C3N4. Rhodamine B (Rh B) aqueous solution was taken as the target pollutant, and the result presented that both imidazole modification and the Z-scheme heterojunction construction benefited from significant enhancement in photocatalytic activity. Moreover, it is revealed that electrons were transferred from imidazole-modified g-C3N4 to SnO through the interface of the composite by XPS analysis. Under visible light (>420 nm) irradiation, the built-in electric field, band edge bending, and Coulomb interaction work synergistically to drive the recombination of relatively useless electrons and holes in the hybrid. As a result, the residual electrons and holes, which possess enhanced reducibility and oxidizability, endow the composite with exceptional redox capability. This research can not only deepen our comprehension of designing and fabricating innovative Z-scheme heterojunction photocatalysts but also presents an effective approach to tackle environmental pollution issues in the future.