Porous AgPd Nanomushrooms with Enhanced Methanol Tolerance for Oxygen Reduction Reaction

Efficient oxygen reduction reaction (ORR) electrocatalysts with high methanol tolerance are essential for the development of direct methanol fuel cells. Herein, a novel synthesis method is presented for the production of porous AgPd nanomushrooms with adjustable Ag/Pd atomic ratios using a seed-mediated epitaxial etching process. These Ag1Pd1 nanomushrooms display superior methanol tolerance in the ORR compared to other AgPd nanocrystals and commercial Pd/C catalysts. Specifically, the ORR activity of Ag1Pd1 nanomushrooms is observed to be nine times higher than that of commercial Pd/C when tested in an O2-saturated 5 m methanol solution. Theoretical calculations suggest that the appropriate Ag/Pd atomic ratio in the nanomushrooms enables a balanced adsorption energy for both O2 and CH3OH, thereby achieving enhanced ORR activity and methanol tolerance simultaneously. This research introduces a new approach to the design of efficient ORR catalysts with high methanol tolerance. Porous AgPd nanomushrooms with adjustable Ag/Pd atomic ratios are synthesized using a seed-mediated epitaxial etching process, showing the superior methanol tolerance in the ORR compared to commercial Pd/C catalysts.image (c) 2024 WILEY-VCH GmbH