Highly Selective\nDual-Atom Pd Heterogeneous Catalyst\nPrepared by Size-Selected Cluster Beam

Atomic dispersed heterogeneous catalysts have emerged\nas a prominent\nresearch focus in catalysis due to their exceptional atom utilization,\nrobust activity, and remarkable selectivity. However, the design and\nsynthesis of catalysts with a precisely defined atomic number and\nexceptional dispersion still pose significant challenges. In this\nstudy, we employed a magnetron sputtering cluster source equipped\nwith a mass selector to selectively fabricate single-atom, dual-atom,\nand clusters with precise atomic numbers catalysts supported on mesoporous\ngraphitic carbon nitride (mpg-C<sub>3</sub>N<sub>4</sub>). This method\nprovides a universally applicable approach for synthesizing highly\npure diatomic catalysts. Furthermore, the dual-atom Pd catalyst exhibits\nan outstanding turnover frequency of 5819 h<sup>–1</sup> in\nthe hydrogenation of nitrobenzene, surpassing that of both single-atom\nPd and Pd<sub>2057</sub> clusters. Density functional theory calculations\nreveal that excellent hydrogenation performance benefits from the\neasier dissociation of H–H bonds at the atomic geminal Pd<sub>2</sub> sites in the hydrogenation process of nitrobenzene compared\nto that of single-atom Pd and Pd clusters. This work presents a universal\nsynthetic strategy for precisely constructing multimetal atomic centers,\nshowcasing the advantages of geminal metal sites in catalyzing multimolecule-involved\nreactions.