Photocatalytic activity of nanocrystalline ZnO, α-Fe2O3 and ZnFe2O4/ZnO

M N Zulfiqar Ahmed,H Nagabhushana,K B Chandrasekhar,B M Nagabhushana,A A Jahagirdar

doi:10.1007/s13204-014-0395-1

Abstract

Nanocrystalline powders of ZnO, α-Fe2O3 and ZnFe2O4/ZnO were prepared by solution combustion method. The characterization of the nano powders was done by powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The ZnO and α-Fe2O3 nanopowders exhibited the wurtzite and hexagonal phases, respectively. The PXRD pattern of ZnFe2O4/ZnO indicated the spinel phase of zinc ferrite and wurtzite phase of zinc oxide. The three nanopowders were used as photocatalysts for the removal of the azodye brilliant yellow (BY) from its aqueous solution. A comparison of the results indicated that ZnFe2O4/ZnO showed better photocatalytic activity for the removal of BY than ZnO and α-Fe2O3. This was attributed to the synergistic effect between ZnFe2O4 and ZnO resulting in better charge separation and reducing the electron–hole recombination. The photocatalytic activity followed the order: ZnO < α-Fe2O3 < ZnFe2O4/ZnO.

Highlights

The world is facing the problem of proper disposal of various products and by-products of dye industries
A comparison of the results indicated that ZnFe2O4/ZnO showed better photocatalytic activity for the removal of brilliant yellow (BY) than ZnO and a-Fe2O3
ZnO, a-Fe2O3 and ZnFe2O4/ZnO were successfully prepared by solution combustion method

Summary

Introduction

The world is facing the problem of proper disposal of various products and by-products of dye industries. It has been reported that about 10–15 % of these dyes are released into the water after the dyeing process (Wanchanthuek and Nunrung 2011). The various physical and chemical processes that are employed for the removal of dyes from textile effluents include precipitation, adsorption, air stripping, flocculation, reverse osmosis and ultrafiltration. These techniques are, nondestructive due to the fact that they only transfer the non-biodegradable matter into sludge giving rise to new type of pollution which needs further treatment (Kansal et al 2007)

Methods

Results

Conclusion