High activity and selectivity of single palladium atom for oxygen hydrogenation to H2O2

Nanosized palladium (Pd)-based catalysts are widely used in the direct hydrogen peroxide (H₂O₂) synthesis from H₂ and O₂, while its selectivity and yield remain inferior because of the O-O bond cleavage from both the reactant O₂ and the produced H₂O₂, which is assumed to have originated from various O₂ adsorption configurations on the Pd nanoparticles. Herein, single Pd atom catalyst with high activity and selectivity is reported. Density functional theory calculations certify that the O-O bond breaking is significantly inhibited on the single Pd atom and the O₂ is easier to be activated to form *OOH, which is a key intermediate for H₂O₂ synthesis; in addition, H₂O₂ degradation is shut down. Here, we show single Pd atom catalyst displays a remarkable H₂O₂ yield of 115 mol/gPd/h and H₂O₂ selectivity higher than 99%; while the concentration of H₂O₂ reaches 1.07 wt.% in a batch.