The Interfacial Interpenetration\nEffect for Controlled\nReaction Stability of Palladium Catalysts

Tailoring well-defined interfacial structures of heterogeneous\nmetal catalysts has become an effective strategy for identifying the\ninterface relationships and facilitating the reactions involving multiple\nintermediates. Here, a particle–particle heterostructure catalyst\nconsisting of Pd and copper oxide nanoparticles is designed to achieve\nhigh-performance alkaline methanol oxidation electrocatalysis. The\nstrong coupling particle–particle heterostructure catalyst\ninduced a unique interfacial interpenetration effect to improve the\ninterfacial charge redistribution and regulate the <i>d</i>-band structure for optimizing the adsorption of CO intermediates\non the catalyst. The resulting catalyst shows impressive mass activity\n(4.0 A mg<sub>Pd</sub><sup>–1</sup>) and current density (215.8\nmA cm<sup>–2</sup>) for the methanol oxidation reaction (MOR)\nin alkaline media, which is 80.0 and 154.1 times higher than 10% Pd/C.\nThe catalyst also exhibited outstanding stability for the MOR without\nobvious mass activity decay after 30,000 cycles. Experimental results\nand theoretical simulation (DFT) studies show that the chemical bond\nof the Cu–O–Pd interface can be regulated by the Pd\npenetration effect, greatly improving the activity and stability of\nthe MOR. The present work exhibits the superiority of the metal particle–metal\noxide heterostructure interface toward the rational design of advanced\nelectrocatalysts.