Incorporation of Ag-doped ZnO nanorod through Graphite hybridization: Effective approach for degradation of Ciprofloxacin

Abstract

To remove the Ciprofloxacin (CIP) from aqueous solution, ZnO–Ag-Gp nanocomposite exhibited efficient photocatalytic properties. The biopersistent CIP is pervasive in surface water and also hazardous to human and animal health. This study utilized the hydrothermal technique to prepare Ag-doped ZnO hybridizing Graphite (Gp) sheet (ZnO–Ag-Gp) to degrade pharmaceuticals pollutant CIP from an aqueous medium. The structural and chemical compositions of the photocatalysts were determined by XRD, FTIR and XPS analysis. FESEM and TEM images revealed the nanorod ZnO with round shape Ag distributed on a Gp surface. The reduced bandgap of the ZnO–Ag-Gp sample enhanced the photocatalytic property which was measured by using UV–vis Spectroscopy. Dose optimization study found that 1.2 g/L is optimum for single (ZnO) and binary (ZnO-Gp and ZnO–Ag), where 0.3 g/L ternary (ZnO–Ag-Gp) exhibited maximum degradation efficiency (98%) within 60 min for 5 mg/L CIP. Pseudo 1st order reaction kinetics rate was found highest for ZnO–Ag-Gp (0.05983 min−1) and it decreased to 0.03428 min−1 for annealed sample. Removal efficiency decreased to only 90.97% at 5th run and hydroxyl radicals played a vital role to degrade CIP from aqueous solution. UV/ZnO–Ag-Gp will be a promising technique to degrade wide-ranging pharmaceutical antibiotics from the aquatic medium.

Keywords

• Advanced Oxidation Process
• Ciprofloxacin
• Degradation
• Graphite hybridization
• ZnO Nanorod