Stable Universal-pH Electrocatalytic Strategy for Efficient Organic Mineralization via Sustained Hydroxyl Radical Generation

Wastewater purification is critical for environmental protection and human health. A significant challenge lies in the lack of efficient and stable electrocatalysts for generating hydroxyl radicals (•OH), the key species for mineralizing pollutants, across the entire pH range. Conventional electrodes face a performance dilemma: classic anodes (e.g., PbO₂, SnO₂) operate only in neutral conditions, while stable precious metal electrodes (e.g., IrO₂, RuO₂) suffer from low •OH yield due to facile oxygen evolution. To overcome this, we developed a universal-pH electrochemical reactor centered on a novel metalloidal boron/diamond matrix (MB/DM) anode. This system achieves efficient •OH generation with exceptional long-term stability over an ultrawide pH range of 0-14. We attribute this universal performance to three key innovations: (1) the anode's intrinsic chemical inertness conferring resistance to extreme H⁺/OH^- corrosion, (2) its high oxygen evolution overpotential promoting •OH accumulation, and (3) a sustained •OH generation kinetics as revealed by our density functional theory (DFT) calculations of the pH-dependent reaction pathway (*H₂O → •OH → *O). This work overcomes the pH limitation in electrochemical water remediation, providing a reliable platform for treating a diverse range of industrial wastewaters.