Tailoring dual S-Scheme based g-C3N4/ZnO/TiO2 ternary photocatalytic system immobilized on floating cork for environmental remediation

Background: Light harvesting and reusability are the key factors for highly effective solar photocatalysis. Floating photocatalysts can maximize light utilization and be recycled easily, making them a strong candidate for real-world environmental applications. Methods: In this article, a novel dual s-scheme-based g-C3N4/ZnO/TiO2/Cork photocatalyst was constructed via a co-precipitation process followed by physical blending of the floating materials. In g-C3N4/ZnO/TiO2/Cork photocatalyst, cork acted as a floating substrate to enhance light exposure, oxygen availability, and reusability. The dual S-scheme charge transfers between g-C3N4, ZnO, and TiO2 improves carriers' charge separation and concentration. Advanced Spectral techniques were utilized to compare and analyze the morphological, structural, and optical characteristics. The photocatalytic activity was further analyzed by using methyl orange (MO) and doxycycline hydrochloride (DCl) as target pollutants. Significant findings: The g-C3N4/ZnO/TiO2/Cork heterojunction exhibited excellent photodegradation activity against MO dye (98.25 %) and DCl antibiotic (79.27 %) within 60 min under visible light. The scavenger experiment revealed that the O-center dot(2)- and (OH)-O-center dot radicals were the major reactive species in this photocatalytic experiment. Additionally, a better recyclability was also demonstrated by the g-C3N4/ZnO/TiO2/Cork heterojunction photocatalyst.