Photoassisted degradation of endocrine disruptors over CuOx–FeOOH with H2O2 at neutral pH

CuOx-doped α-FeOOH (CuOx–FeOOH) nanorods were synthesized by controlling the reaction between ferrous sulfate, cupric sulfate and sodium borohydride at ambient atmosphere. The resulting materials were characterized by transmission electron microscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. CuOx–FeOOH was mainly composed of α-FeOOH and CuOx (CuO and Cu2O). The catalyst was found to be highly effective for the degradation of endocrine disruptors, including dimethyl phthalate, 2,4-dichlorophenoxyacetic acid, and 2,4-dichlorophenol in the presence of H2O2 and UVA at neutral pH. By the total organic carbon and GC–MS analysis, the degradation process of DMP was shown to proceed with the cleavage of C–O bond in ester linkages and the phenyl ring opening into organic acids and CO2. The studies of OH formation and cyclic voltammetry revealed that the H2O2 was decomposed into OH or O2 by the promotion of metal oxide. The obtained results showed that the synergistic effect between CuOx and α-FeOOH markedly enhanced the H2O2 decomposition into OH in CuOx–FeOOH suspension, causing the higher catalytic reactivity. A possible reaction mechanism was proposed.