Enhanced H 2 O 2 Generation via Two-Electron Water Oxidation on Multilayer Network BDD: Performance and Mechanistic Insights

Hydrogen peroxide (H2O2) is an environmentally benign yet versatile oxidizing agent with broad applications across academic and industrial fields, including sterilization, sewage treatment and chemical synthesis. The electrochemical two-electron water oxidation (2e- WOR) pathway as an effective method for in situ electrosynthesis of H2O2, is not only environmentally friendly and economical, but also can be combined with appropriate reduction reactions to achieve the large-scale synthesis of high-value-added chemicals. This paper reports the preparation of three different boron-doped diamond (BDD) electrodes by hot filament chemical vapor deposition (HFCVD) on titanium (Ti) plate/multilayer network Ti woven mesh substrates. The multilayer network BDD electrodes (MN-BDD15 and MN-BDD9) exhibited significantly larger electrochemically active surface areas than the flat plate BDD electrode (BDD9), measuring 28.00 and 16.70 times that of BDD9, respectively. Correspondingly, the electron transfer resistances (Rct) for BDD9, MN-BDD9 and MN-BDD15 were determined to be 57.90, 0.79, and 0.54 Ω, respectively. Notably, the MN-BDD15 electrode demonstrated superior performance, achieving a Faradaic efficiency (FE) of 25.70% at a current density of 20 mA cm–2. Further analysis confirmed that both hydroxyl radical (•OH) production and mass transfer efficiency was dramatically enhanced in MN-BDD15 compared to BDD9. Under identical conditions, the H2O2 yield of MN-BDD15 was 15.00 times higher than that of the BDD9, proving that the multilayer network BDD is a promising high-performance electrode material for efficient electrocatalytic oxidation synthesis of H2O2.