H‐Bonds in Carbon Quantum Dot‐anchored C3N5 to Boost Proton‐Coupled Electron Transfer for Piezoelectric‐Driven Hydrogen Peroxide Synthesis under Ambient Conditions

Tuning proton‐coupled electron transfer (PCET) is a promising strategy to boost the oxygen reduction reaction (ORR) for H2O2 synthesis, but the slow transmission rate of protons and electrons to active sites remains a significant bottleneck. To address this, we developed an H‐bond‐driven PCET process based on carbon quantum dotanchored C3N5 (CQDs‐C3N5) for piezo‐catalytic H2O2 synthesis. CQD‐C3N5 exhibited a remarkable piezo‐catalytic synthesis rate of 5025 μmol g⁻¹ h⁻¹ under ambient conditions. This efficiency is attributed to H‐bonds between CQDs and C3N5, which accelerate PCET in the ORR. The piezoelectric‐generated charges, from the dipole field of the C3N5 plane and protons in water, were rapidly transferred to the C rings of CQDs via H‐bonds. This process facilitated the adsorption of oxygen onto C2 sites adjacent to carboxyl groups of CQDs, which in turn led to the formation of H2O2 through a rapidly protonated, indirect 2e− pathway. Additionally, a piezo‐self‐Fenton reaction system was constructed for oxytetracycline‐rich wastewater purification, with effectively effects on chemical oxygen demand, antibiotic‐resistant bacteria and antibiotic‐resistant genes degradation. This study highlights the critical role of H‐bond networks for tuning PCET in the ORR and provides a comprehensive understanding for the precise control of catalytic reaction kinetics through molecular structural engineering.