A Comparative Study of Edge-Selective and Face-Specific Growth of PdAg Alloys on Au Nanoplates and Their Applications for Ethanol Oxidation Reaction

We present the synthesis of two-dimensional Au-PdAg hybrid electrocatalysts with two distinct morphologies through site-specific deposition in seeded growth. The co-reduction of Pd and Ag precursors in the presence of plate-like Au seeds, using CTAC and CTAB as capping agents, led to edge- and face-specific deposition. This approach successfully and selectively engineered the interface between Au and PdAg phases along the edge region and upper/bottom faces, respectively. Our results demonstrate that the Au-PdAg products exhibit superior electrocatalytic activity and long-term durability for ethanol oxidation in alkaline media compared to commercial Pt/C electrocatalysts. DFT simulations further validated the advantages of constructing Au-PdAg interfaces over alloyed counterparts in EOR electrocatalysis. The current study offers a viable strategy for constructing two-dimensional trimetallic EOR electrocatalysts with well-defined interfaces, potentially paving the way for the rational design of high-performance fuel cell catalysts.