Mo2N Enhanced Fenton-Like Process: Role of Mo Reducibility and N Adsorption

Molybdenum nitride, because of the strong metal-support interaction between nitrogen and the metal, exhibits activity superior to that of bare metals, demonstrating its effectiveness as a co-catalyst to address the slow kinetics of the iron reduction in the Fenton process. Here, we introduced Mo₂N as a co-catalyst to accelerate the cycles of Fe³⁺/Fe²⁺ within a Fenton-like system consisting of Fe³⁺ and H₂O₂, thereby enhancing the activation of hydrogen peroxide to generate reactive oxygen species (ROS). The system demonstrates excellent recyclability and stability. XPS spectroscopic analyses reveal that Mo(III) and Mo(IV) species on the Mo₂N surface are capable of reducing free Fe(III), while FTIR analyses show nitrogen (N) and nitrogen oxide (NO_x) facilitate the adsorption and coordination of iron. Both homogeneous and heterogeneous reduced iron species are active in the activation of H₂O₂. EPR spectroscopy further confirms that the primary ROS generated are hydroxyl radicals (·OH) and superoxide anions (·O₂⁻). This study not only underscores the feasibility of Mo₂N-based Fenton-like systems but also provides a new strategy for promoting the practical application of Fenton chemistry.

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