Tailored Polymeric Carbon Nitride Coupled with Bi2O3 for Constructing Z‐Scheme Heterojunction with Enhanced Photocatalytic Activity

Abstract

The great demand for visible‐light‐induced catalysts with high photocatalytic performance has stimulated extensive interest in constructing g‐C3N4‐based Z‐scheme heterojunctions. In this research work, we constructed the g‐C3N4/Bi2O3 Z‐scheme heterojunction by precipitation‐hydrothermal method, and confirmed the close contact interface between g‐C3N4 and Bi2O3 to form the heterojunction by various characterization techniques, which facilitates the efficient separation of photogenerated electrons‐holes. Compared to pure g‐C3N4 and Bi2O3, the g‐C3N4/Bi2O3‐1 composite exhibited a transient photocurrent response approximately 7 and 5 times higher than that of g‐C3N4 and Bi2O3, respectively, with stronger visible photocatalytic activity and degraded 99.8% methylene blue within 75 min. Ion trapping experiments showed that •OH free radical had the greatest effect on the degradation of methylene blue, while •O2‐ and h+ had less effect. According to the experimental test results, the possible photocatalytic degradation mechanism of g‐C3N4/Bi2O3‐1 catalyst was proposed. This study provides a new avenue for the development of novel g‐C3N4‐based Z heterojunction materials with application value.