Accurate construction of Cd/CdS/g-C3N4 heterojunction interface for efficient photocatalytic tetracycline degradation and Cr6+ reduction

Abstract

With the increasing attention paid to environmental issues and the rapid development of photocatalytic environmental remediation technology, it is of great significance to develop catalysts with efficient photocatalytic environmental remediation capabilities. Graphite phase carbon nitride and its heterojunction are ideal choices for photocatalytic environmental remediation. Accurately constructing stable and well contacted heterogeneous interfaces is an effective means to improve catalytic efficiency. Herein, stable Cd/CdS/CN heterojunction interface was successful constructed by an in-situ synthesis method. Cd/CdS/CN photocatalysts exhibits excellent environmental remediation potential, capable of removing 88 % of high concentration TC (40 mg/L) within 60 min, and reducing over 96 % of Cr(VI) (50 mg/L) within 25 min under visible light, with good cycling stability. In addition, the reaction mechanism and TC degradation pathway of the composite photocatalyst with good photocatalytic activity were analyzed in depth. The experimental results confirmed that the synergistic effect of Z-Scheme heterojunction and Ohmic junction significantly improved the separation and migration of photogenerated carriers in the system, and maintained a high redox ability. This work provides a new reference for constructing CN based heterojunction photocatalysts with close contact.