A novel core-shell Z-scheme heterojunction In2O3@BiFeO3 with broad spectrum response for enhanced photocatalytic degradation of tetracycline

Photocatalysis is proven as a desirable technology for elimination of the tetracyclines pollutant from wastewater. Herein, a novel core-shell Z-scheme heterojunction In2O3@BiFeO3 was, for the first time, fabricated via facile hydrothermal method to effectively eliminate tetracycline in wastewater. The prepared photocatalysts were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), UV-vis spectroscopy and so on. The photocatalytic performance of the prepared samples was evaluated by photo-degradation of tetracycline (TC) under visible light. TC degradation results demonstrated that the as-prepared In2O3@BiFeO3 obeyed the pseudo-first-order kinetics and exhibited a higher photocatalytic rate of 0.01173min(-1) that was approximately 2.97 and 14.4 folds those of the raw BiFeO3 and In2O3, respectively. Additionally, In2O3@BiFeO3 possessed high stability during five consecutive cycles. The core-shell structure and the photosensitization of BiFeO3 significantly improved light-absorption in the entire visible region. The enhanced photocatalytic activity is attributed to the improved light harvesting and the effective separation of photogenerated electron-hole pairs due to the formation of core-shell Z-Scheme heterojunction. Due to the well-matched band position of In2O3 and BiFeO3, center dot OH, center dot O-2(-) and h(+) all act as primary reactive species in TC degradation. This research provides a new strategy to construct the promising visible-light-driven photocatalyst for environmental remediation.

Automated summary

A core-shell Z-scheme heterojunction In2O3@BiFeO3 was synthesized via a facile hydrothermal method, showing excellent photocatalytic performance for the degradation of tetracycline in wastewater under visible light. The enhanced photocatalytic activity is attributed to the improved light harvesting and the effective separation of photogenerated electron-hole pairs. This study provides a new strategy for constructing promising visible-light-driven photocatalysts for environmental remediation.