Fabrication of Co + F Doped ZnO Films for Improved Visible Light Responsive Photocatalysis

Abstract

The aim of this work is to investigate the efficacy of nebulizer sprayed ZnO–Co–F thin films for degrading the methylene blue (MB) aqueous solution under visible light irradiation. The physical properties of the prepared samples like structural, surface morphological and optical properties are studied using X-ray diffractometer (XRD), Scanning Electron Microscope (FESEM), UV-vis NIR spectrometer, spctroflurometer (PL) and Fourier Transform Infrared spectrometer (FTIR). The photocatalytic studies revealed that ZnO–Co–F film exhibited superior degradation efficiency over ZnO–Co and ZnO against MB as evinced by the degradation rate constants, 0.0782, 0.0475 and 0.0289 min^–1, respectively. This study showed that Co + F doping helps to remove the major limitations of ZnO and thereby leads towards better visible light activity. The structural and optical studies revealed the proper incorporation of Co²⁺ and F^– ions into the ZnO lattice and the reduction in band gap. PL emission confirmed that Co + F doping reduces the electronhole recombination rate and increases the availability of free carriers.