Ultrastable copper superatom for CO2-to-C2+ electrocatalysis enabled by electronic and ligand-shell stabilization

Copper nanoclusters are attractive low-cost candidates for catalysis, yet their practical development has long been limited by the intrinsic instability of Cu(0)-containing species. In a recent Journal of the American Chemical Society study, Wang and co-workers report a landmark advance: the first 6-electron superatomic copper nanocluster, [Cu 45 H 6 (C≡CR) 18 (OAc) 15 ] (Cu 45 , OAC = OOCH 3 ), which exhibits unusual chemical and thermal robustness. Single-crystal X-ray diffraction and density functional theory calculations link this robustness to a closed-shell superatomic configuration (1S 2 1P 4 ) and strengthened copper–ligand interactions, aided by a rigid protective shell. Remarkably, this ultrastable and structurally precise Cu superatom also serves as a well-defined electrocatalyst for electrocatalytic CO 2 reduction reactions (eCO 2 RR) toward CO 2 -to-C 2 H 4 conversion, delivering high C 2+ selectivity and enabling mechanistic interrogation of C–C coupling on a molecularly defined Cu(I)/Cu(0) interface. Cu 45 reaches a peak faradaic efficiency (FE) for C 2+ of 81.8% (FE C2H4 = 58.4%) at − 1.6 V RHE and sustains activity for ~ 11 h. This work establishes design principles for robust copper superatoms and opens new opportunities for cluster-enabled CO 2 valorization. Graphical abstract An atomically precise 6-electron Cu 45 superatomic nanocluster with exceptional stability and Faradaic efficiency exceeding 80% for CO 2 -to-C 2+ conversion, offering a novel platform for electrocatalysis.