2D/2D nitrogen-rich graphitic carbon nitride coupled Bi2WO6 S-scheme heterojunction for boosting photodegradation of tetracycline: Influencing factors, intermediates, and insights into the mechanism

A novel two-dimensional 2D/2D Bi2WO6@g-C3N5 (BiW@CN) step-scheme (S-scheme) heterojunction was designed and fabricated via simple wet chemical approach. The crystal structure, morphology, composition, and optical properties were systematically investigated by multiple techniques. Apparently, BiW@CN heterojunction when compared to bare g-C3N5 and Bi2WO6 has remarkable light-harvesting capability and exhibits better photocatalytic performance toward tetracycline degradation. The excellent enhancement activity of the BiW@CN is due to the formation of S-scheme heterojunction, which not only promotes the spatial charge separation but also endows the reduction power of photogenerated electrons. Notably, the S-scheme charge transfer mechanism was explored by quenching experiments, electron spin resonance, and X-ray photoelectron spectroscopy analysis. Finally, the study proposes possible TC degradation pathways by identifying the transformation products. This research provides a new platform for efficient 2D/2D S-scheme heterojunctions for environmental water pollution treatments. [Display omitted] •BiW@CN heterojunction photocatalyst was fabricated via simple wet chemical approach.•Photocatalytic performance of BiW@CN was remarkably boosted under the visible light.•TC degradation pathway was examined through LC-MS identifying transformation products.•The S-scheme charge transfer mechanism of the BiW@CN nanocomposite was corroborated.