Fe-doped Al2O3 nanoplatforms as efficient and recyclable photocatalyst for the dyes remediation

Abstract

γ-Al2O3 nanowires (NW) were synthetized and impregnated with different amounts of iron (2, 6 and 10 wt%). Catalysts were further characterized by powder X-ray, Fourier transform infrared spectroscopy, nitrogen adsorption–desorption isotherms, UV–visible diffuse reflectance, temperature-programmed reduction, thermogravimetric analysis, transmission electron microscopy, X-ray photoelectron spectrometry and atomic absorption. The obtained materials were evaluated as heterogeneous photocatalysts in the degradation of azo dye methyl orange as model compound employing a 125 W high-pressure mercury lamp. After 240 min under irradiation the complete decoloration and 69% of mineralization was obtained when Fe6NW was employed. When commercial γ-Al2O3 was employed as support of 6 wt%. of iron and evaluated in photodegradation the final decoloration reached up to only 46%. Reaction parameters such as iron amount, catalyst amount, pH, effect of support and reuses, were evaluated. The photocatalyst was employed for five consecutive reaction cycles with only a 10% of diminish of activity, resulting in an attractive low-cost and benefit in heterogeneous catalysis.