Ternary supportless Pd@Cd-Ag core-shell as advanced nanocatalysts towards electro-oxidation performance of ethanol

Abstract

Developing highly active Pd-based nanocatalysts with a well-organized structure is desired for direct alcohol fuel cell commercialization. In this study, room temperature seed mediated growth strategy has been successfully developed to prepare ternary [email protected]x-Agy core-shell as advanced novel non-Pt anode nanocatalysts for ethanol oxidation reaction EOR in alkaline electrolyte. The introduction of oxophilic Cd and Ag metals into Pd nanocatalysts can reduce the adsorption energy of OHads on the [email protected]x-Agy nanocatalysts and inhibit the COads on the Pd surface. Morphological characterization demonstrates that the as-synthesized [email protected]x-Agy nanocatalysts are well-organized core-shell nanostructure with Pd NPs as the core and Cd-Ag alloy as the shell. Moreover, electrochemical results indicate that the [email protected]1-Ag1 core-shell catalyst exhibit a remarkable electrochemical activity (2995.76mAmgPd−1), excellent CO tolerance and long-term durability compared to those of [email protected] (1285.9mAmgPd−1), [email protected] (2423.52mAmgPd−1) and commercial Pd/C (JM) (477.4mAmgPd−1) nanocatalysts. The excellent catalytic activity and stability of [email protected]1-Ag1 nanocatalyst can be associated to their huge electrochemical active surface area, positive influence of Cd-Ag NPs on Pd NPs and the unique well-organized core-shell nanostructure. These results suggested that the as-synthesized [email protected]Cdx-Agy core-shell could serve as advanced catalysts towards alkaline DEFCs.