Iron oxidation/titanium dioxide as a highly active photocatalyst for degradation of 2,4-dichlorophenoxyacetic acid herbicide

Abstract

Photocatalysis has been considered as one green approach for environmental remediation for water contamination. Although titanium dioxide (TiO2) photocatalyst has been established for degradation of organic pollutants, high recombination rate of charge carriers limits its photocatalytic activity1-2. Therefore , modification of Ti02 will be very critical and the added modifier should be an environmentally safe and sustainable material. One of the potential modifiers is iron oxide (Fe2O3) co-catalyst, which is non-toxic and abundantly found in the Earth. In this work , we reported the improved photocatalytic activity of Ti02 for degradation of 2,4-D ichlorophenoxyacetic acid (2,4-D) herbicide by addition of Fe2O3 co-catalyst through an impregnation method. Photocatalytic testing under 1 h of UV light irradiation showed that low loading amount of Fe2O3 improved activity of Ti02for degradation of 2,4-D for ca. 5 times (Fig.1). While the optical properties of TiO2 was not much influenced by the addition of Fe2O3, the fluorescence study suggested that the optimum loading amount of Fe2O3 reduced the elect ron-hole recombination on TiO2 without blocking.