Abstract
•Zeolitic imidazolate framework-8 derived nano ZnO with surface area of 1465 m2g–1.•Loading of 1.0‒4.0 wt.% CuO to ZnO forming p-n hetrojunction photocatalyst.•CuO reduce bandgap to 2.63 eV and upsurge light absorption and charge separation.•Photooxidation of tetracycline enhanced by 28 times compared to ZnO.•Complete removal of tetracycline obtained after 45 min with 1.5 gL–1 of 3%CuO@ZnO.
Nanostructured photocatalysts represent an eco-friendly material for photooxidation of toxins beneath light radiation. However, the surface structure and large bandgap energies are the main issues for realizing these photocatalysts under visible-light operation. Herein, we obtain high surface area ZnO by the calcination of solution-prepared zeolitic imidazolate framework (ZIF-8). Also, the ZIF-8 is loaded with Cu precursor to obtain 1.0 − 4.0 wt.% CuO@ZnO p-n heterojunctions by an additional calcination process. The CuO loaded on derived ZnO fashioned a mesoporous texture with an extreme surface area of 1485 m2 g‒1. The introduction of CuO to ZnO exposed a broader light absorption and bandgap reduction to 2.63 eV from 3.43 eV for ZnO and a significant increase of the surface area to 1665 m2 g‒1 for the 3.0 wt.% CuO-loaded ZnO. The fabricated CuO@ZnO employed for tetracycline's (TC) photooxidation, as an antibiotic target in water systems. The optimal 3.0 wt.% CuO@ZnO performed a complete TC photooxidation within 45 min with an oxidation rate of 113.5 × 10−3 min−1 at a dose of 1.5 gL−1. This heterojunction exhibited exceptional recyclability for five cycles. The high activity is regarded to the extreme surface area and the migrated photoinduced charges within the CuO@ZnO.
[Display omitted]