Enhanced photocatalytic degradation efficiency of ciprofloxacin in aqueous media of Co<sup>2+</sup> ion-modified MgAl-hydrotalcite materials using activated persulfate

Sets of MgAl-hydrotalcite materials modified with Co2+ ions were synthesized by the co-precipitation method. The characterization results showed that the synthesized material samples had a hydrotalcite-like structure, and the lamellar order decreased when the amount of Co2+ ions substitution increased. However, the absorption edges of the modified samples shifted strongly to the visible region, and the band gap energy decreased significantly from 3.56 eV for MgH sample to 1.54 eV for 3.0CoMgH sample, enhancing the catalytic activity of the modified materials. The 1.5CoMgH sample had the highest CIP 25 ppm treatment efficiency (reaching around 84 - 86% after 240 minutes of illumination using 0.2N persulfate activation). Additionally, the 0.5CoMgH sample had the highest CIP 20 ppm photodegradation efficiency, reaching about 50% of the total treatment efficiency of about 88.6%.