Ag/Ce0.5Zr0.5O2 nanofibers: Visible light photocatalysts for degradation of p-nitrophenol

Abstract

Ag deposited Ce0.5Zr0.5O2 nanofibers (CeZr-NF) were successfully synthesized by impregnation of Ag (0.5, 1.0, 1.5 and 2.0 wt.%) over CeZr-NF and thermal treatment at 500°C. The prepared Ag/CeZr-NF nanocomposites were analyzed by elemental analysis, XRD, Raman, FE-SEM, DR UV-vis, XPS and N2-adsorption measurements. The obtained results indicated that highly distributed Ag species were formed on the surface of CeZr-NF semiconductor because of strong interaction. The obtained Ag/CeZr-NF nanocomposites displayed excellent photocatalytic activity for degradation of p-nitrophenol (p-NP) activities under visible irradiation, compared to Ag metal, Ag oxides and CeZr-NF individually. The optimization of reaction parameters was performed by studying the influence of pH of solution, reaction time and catalyst amount on the p-NP degradation efficiency. The highest degradation efficiency of 96% was observed with acidic p-NP solution and catalyst mass of 0.2 g in 90 min for 1.5 wt.% Ag loaded CeZr-NF sample. Significant enhancement in degradation efficiency of the CeZr nanofibers after Ag deposition is because of the combination effects of low band gap energy, large pore size, high photocurrent density and slow e−-h+ recombination. After five recycles, the photocatalytic activity of Ag/CeZr-NF nanocomposites did not decline indicating the robust nature of synthesized composites.