ZnSnO@Ti ceramic film anode preparation by microarc oxidation for 2e WOR degradation of unsymmetrical dimethylhydrazine (UDMH).

The main challenge facing the anodic electro-Fenton through the 2e water oxidation reaction (WOR) for toxics degradation lies in the electrode's stability, because the anodic oxygen evolution (OER) generated O will inevitably exfoliate the electro-active components loaded on the electrode substrate. To address this point, two aspects need attention: 1) Identifying a catalyst that exhibits both excellent electrocatalytic activity and selectivity can improve the faradaic efficiency of hydrogen peroxide (HO); 2) Employing novel methods for fabricating highly stable electrodes, where active sites can be firmly coated. Consequently, this study utilized microarc oxidation (MAO) to prepare a ceramic film electrode ZnSnO@Ti at 300 V. ZnSnO acts as an WOR electrocatalyst and further improved the generation of HO for treating real wastewater containing Unsymmetrical Dimethylhydrazine (UDMH). From the perspective of characterization of electrode structure, ZnSnO@Ti forms a stable active coating, the electrochemical yield of HO is high up to 78.4 μmol h cm, and the selectivity of HO is over 80% at 3.3 V vs. RHE, which can be fully applied to scenarios where it is inconvenient to transport HO and need in-situ safe production. Additionally, the prepared electrodes exhibit significant stability, suitable for various applications, providing insightful preparation strategies and experiences for constructing highly stable anodes.