3D flower-like In₂Se₃/Bi₂O₂CO₃ n-n scheme heterojunctions for visible-driven simultaneous degradation of multi-tetracyclines

ABSTRACT

The purification of tetracycline wastewater using visible-light-driven heterojunction catalysts is a promising approach. In this study, a n-n type heterojunction, In₂Se₃/Bi₂O₂CO₃, is synthesised through a solvothermal method by combining band-matched semiconductors. The resulting hybrid has a 3D hierarchical structure with abundant mesopores, facilitating rapid mass transfer. Notably, 5% In₂Se₃/Bi₂O₂CO₃ hybrids demonstrate enhanced photocatalytic efficacy for simultaneous degradation of tetracycline hydrochloride (TCH) under visible light, including TCH blends with chlortetracycline (CTC) and oxytetracycline (OTC). This enhancement originates from the heterojunction interface, narrowing the band gap, increasing visible light absorption by Bi₂O₂CO₃ (BOC), and creating an inherent electric field between BOC and In₂Se₃, separating electron-hole pairs. Mechanistic analysis identifies h⁺ and •O₂⁻ radicals as primary contributors to the photocatalytic process, suggesting a plausible n-n mechanism. This innovative design shows promise for advancing hierarchical heterostructures in tetracycline removal.

KEYWORDS:

• Heterojunction structure
• In₂Se₃/Bi₂O₂CO₃
• photocatalytic
• wastewater purification
• phytotoxicity

Disclosure statement

No potential conflict of interest was reported by the author(s).