An Fe–Mn binary oxide (FMBO) modified electrode for effective electrochemical advanced oxidation at neutral pH

Fe-Mn binary oxide (FMBO)/activated charcoal (AC) is blended with carbon black (CB) for use as a dual function catalyst for the effective removal of organic pollutants at neutral pH via electro-Fenton-like oxidation. CB, which is composed of micropores and mesopores, acts as an oxygen reduction catalyst to produce H2O2, and the evenly distributed FMBO nanoparticles effectively catalyze the production of hydroxyl radicals using the on-site generated H2O2. As a result, the FMBO-modified electrode exhibits a high catalytic efficiency over a wide pH range from 3–10. The prepared electrode exhibited a hydroxyl radical production rate of 1.3 μM W−1 cm−2 at neutral pH, higher than that obtained with the blank CB electrode and Fe(II) (0.72 μM W−1 cm−2). The removal efficiency of nitrobenzene reached 80 ± 3% at neutral pH with the FMBO/AC/CB electrode compared to 42 ± 7% with Fe(II). The results from various material characterization techniques including X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) confirm that FMBO/AC is bound to poly(tetrafluoroethylene) (PTFE) together with CB in the prepared electrode. These results suggest that electrochemical advanced oxidation using this new FMBO/AC/CB electrode represents a promising approach for organic pollutant removal.