Breaking Coordination Symmetry of Zinc Single Atoms Under Nanoconfinement Enables Ultrafast Electron Transfer in Non-Radical Oxidation.

The application of single-atom catalysts (SACs) based on partially filled 3d orbital metals (e.g., Fe, Co, Cu) in Fenton-like systems faces a fundamental activity-stability trade-off caused by metal leaching and irreversible deactivation during redox cycles. Here we report a coordination-symmetry-breaking strategy that activates inert zinc single atoms via atomic coordination distortion and nanofluidic confinement. Asymmetric Zn-Nx sites integrated within carbon nitride nanochannels form a membrane reactor that couples molecular sieving with oxidation catalysis. The synergy between asymmetric coordination and nanoconfinement creates an efficient electron pathway, enabling direct electron transfer from pollutants to peracetic acid (PAA) through metastable complexes, circumventing radical pathways. This coordination asymmetry induces localized charge polarization, lowering the activation barrier for PAA and resulting in exceptional kinetics (0.09 ms-1) under nanoconfinement, negligible Zn leaching (<0.1 ppm), and strong resilience in complex water conditions. The system achieves industry-leading cost efficiency (0.11 USD/m3) over 100 h operation, outperforming conventional Co SAC. This work establishes a universal design principle integrating atomic symmetry control with nanofluidics to transform inert metals into highly efficient and stable catalytic membranes for sustainable water purification.