Construction of MWCNT-Bridged ternary S-scheme BiVO4/NH2-UiO-66 (Zr) heterojunction for enhanced visible-light photocatalytic degradation of tetracycline

The accumulation of antibiotics in aquatic ecosystems poses a serious threat to the environment and to human health. Tetracyclines (TC) account for a significant proportion of antibiotic residues worldwide. In order to overcome the limitations of conventional degradation methods, we created a three-component S-scheme heterojunction consisting of BiVO 4 /MWCNTs@NH 2 -UiO-66 (Zr) using a two-step solvothermal process. This synergistic integration utilises: (i) MWCNTs as electron transport bridges; (ii) NH 2 -UiO-66 (Zr) for high TC adsorption (surface area of 931.86 m 2  g −1 ); and (iii) BiVO 4 for visible light harvesting. This architecture broadens light absorption, reduces charge recombination and enables dual-pathway Reactive Oxygen Species (ROS) generation. Under visible light, the optimised catalyst achieves 95.2 % TC degradation within 90 min–7.73 times faster than pristine BiVO 4 (k = 0.02721 vs. 0.00352 L mg −1 ·min −1 ). Radical trapping and EPR analyses confirm ·O 2 − and h + as the dominant species, while LC-MS reveals three degradation pathways. With 85.3 % activity retention after five cycles, this work provides a blueprint for the design of efficient, antibiotic-mineralising photocatalysts.