Dual-polarity engineering breaks charge transfer kinetic balances to enhance H2O2-mediated nitrate photosynthesis from air

Sustainable H₂O₂-mediated photocatalytic nitrate synthesis from air faces carrier imbalance due to slow hole transfer and ultrafast electron migration. We overcome this by integrating sulfur/oxygen dual-polarity units into electron-deficient naphthalene diimide (NDI)-based donor-acceptor (D-A) π-frameworks, achieving spatiotemporal electron-hole decoupling. Experimental and theoretical analyses indicate that this dual-polarity architecture gives rise to tandem endogenous electric fields and robust macroscopic polarization, creating spatially separated “electron platforms” and “hole superchannels,” which reduce recombination and accelerate redox kinetics. Crucially, polarization-induced ordered molecular alignment aligns reactant orientations and lowers N≡N dissociation barriers, enabling concurrent oxygen reduction and nitrogen oxidation. The optimized catalyst achieves a record nitrate yield of 8.89 mg g⁻¹ h⁻¹ with an apparent quantum efficiency of 5.50%, outperforming state-of-the-art metal-free systems. Our work introduces innovative design principles and offers a profound perspective for achieving differential bidirectional control over electron and hole carrier transfer rates.