Orbital coupling in bridge-mediated FeCu dual-atom catalysts for water decontamination

Dual-atom catalysts (DACs) hold significant promise for advanced oxidation processes. However, their practical applications are often limited by sluggish electron transfer and low atomic utilization efficiency. Herein, we report that P-bridged Fe-Cu dual-atom catalysts (FeCu-NP-C) are precisely modulated by first-shell N and P ligands, forming a unique N₃Fe-P₁-CuN₃ structure. The Fe-P-Cu bridging bond induces d-p-d gradient orbital coupling to establish a directional electron-transfer channel from the Cu site (electron donor) to the Fe site (electron acceptor) for enabling ultrafast pollutant degradation and bacterial inactivation. The FeCu-NP-C catalyst enables peroxymonosulfate activation to selectively generate high-valent iron-oxo species with a steady-state concentration of 5.80 × 10^-5mM, which is 100 times higher than that of Fe-NP-C. The FeCu-NP-C membrane reactor achieves a treatment capacity of 500 L of wastewater per gram of catalyst over 100 h, at an operational cost of USD 0.16 per tonne. This work provides deep insights into the bridge-mediated orbital interactions of DACs for water decontamination.