Robust and Efficient Pd–Cu Bimetallic Catalysts with Porous Structure for Formic Acid Oxidation and a Mechanistic Study of Electrochemical Dealloying

To obtain highly efficient and robust electrocatalysts for formic acid oxidation, Pd x Cu y /C binary catalysts with porous structures were successfully prepared via electrochemical dealloying. Catalysts with different Pd/Cu atomic ratios were characterized through transmission electron microscopy, inductively coupled plasma atomic emission spectroscopy, and X-ray diffraction. The optimized dealloyed Pd 1 Cu 4 /C catalyst with a porous structure displayed a catalytic activity of 2611 A g −1 and high stability (30.5% activity retention under repeated cyclic voltammetric (CV) patrol), whereas a commercial Pd/C-Aldrich benchmark showed a catalytic activity of 785 A g −1 and retained 16.5% activity. A detailed mechanistic study of electrochemical dealloying was performed. Under repeated CV patrol, Pd-enriched porous architectures evolved from Pd-poor surfaces, accompanied by successive Cu dissolution. Graphical abstract Pd x Cu y /C catalysts were fabricated via a one-pot hydrothermal approach for formic acid oxidation. Mechanism study on the electrochemical dealloying process revealed that the initial Pd-poor surface evolved into porous Pd-enriched architecture due to successive dissolution of Cu. The tentatively optimized D-Pd 1 Cu 4 /C catalyst registered the highest mass activity (2611 A g −-1 ) and specific activity (42.3 A m −-2 ), surpassing that of a commercial Pd/C benchmark (785 A g −-1 , 25.7 A m −-2 ).