Exploring silver oxide-loaded yttrium vanadate nanocomposite for visible-light-driven photooxidation of ciprofloxacin antibiotic in water

Abstract

As a sooner or later risk, antimicrobial resistance due to the overuse of antibiotics is considered a nightmare facing humankind. The visible-light mineralization of antibiotic waste over nanoceramic photocatalysts is an innovative expectant method. Concerning this, nanostructured yttrium orthovanadate (YVO4) is grown via an adapted sol-gel process tracked by loading of 1.0–4.0 wt% of silver oxide (Ag2O) to form heterojunction nanocomposite of Ag2O/YVO4. The as-prepared heterostructures were applied for visible-light photoelimination of ciprofloxacin (CF) in water. The presence of Ag2O has enhanced both light absorbance and photogenerated carrier separation of YVO4. The 3.0 to 4.0 wt% loading of Ag2O designated the thinnest bandgap of 2.4 eV regardless of the minor decrease in their specific surface areas from 220 in bare YVO4 to 168 m2 g−1 for 3.0 % Ag2O/YVO4. The complete mineralization of CF over 3.0 % Ag2O/YVO4 was achieved after 60 min of light illumination at an optimized dose of 1.6 mg mL−1 and a reaction rate constant of 5.41 × 10−2 min−1. This improved photocatalyst has also a recyclable ability of ∼95 % of its initial photoactivity after the fifth experimental run. Therefore, the augmented light harvesting, surface texture, as well as superb carrier separation represent a key role in the performance of Ag2O/YVO4.