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 application is often limited by sluggish electron transfer and low atomic utilization efficiency. Herein, we report that P-bridged Fe-Cu bimetallic catalysts (FeCu-NP-C) were precisely modulated by first-shell N and P ligands, forming a unique N ₃ Fe-P ₁ -CuN ₃ structure. The Fe-P-Cu bridging bond induced 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. FeCu-NP-C activated peroxymonosulfate to selectively generate high-valent iron-oxo species at a concentration of 5.80 × 10 ^− 5 mM, which was 100 times higher than that of Fe-NP-C. Remarkably, the FeCu-NP-C membrane reactor achieved a treatment capacity of 500 L of wastewater per gram of catalyst over 100 h, at an operational cost of US$0.055 per ton. This work provides deep insights into the bridge-mediated orbital interactions of DACs for water decontamination.