Development of a new cathode for the electro-Fenton process combining carbon felt and iron-containing organic–inorganic hybrids

New kinds of electrodes were prepared for implementation in the electro-Fenton process. Based on carbon felt/organic–inorganic talc like hybrid (TLH), the electrodes were successfully prepared by a simple one-step sol–gel procedure at room temperature, from aminopropyltrimethoxysilane, magnesium and iron(III) hexahydrated chlorides, carbon felt, and ethanol. They were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray fluorescence, thermal analysis, scanning electron microscopy, and solid-state nuclear magnetic resonance. It was shown that the order of carbon felt addition to the prepared solution is a key point to form a thin and homogeneous TLH layer at the surface of the carbon fibers. Also, composites having different Fe/Mg molar ratios can be obtained. The composite containing 100 wt % Fe was successfully tested as an electrode for the electro-Fenton process, because 98% degradation yield was obtained after 4 h of electrolysis. These results show that Fenton's reaction can be achieved with immobilized iron and H2O2 produced at the cathode, which can account for the better degradation yield as compared with 70.5% obtained during electrolysis with a nonmodified cathode under the same operating conditions. Consequently, the use of such a material as an electrode for the electro-Fenton process was proven to merit further studies and, notably, to be used for the processing of industrial pharmaceutical effluents.