Pd‐Based Electrocatalysts: Advancing the Efficiency of Ethanol Electro‐Oxidation

ABSTRACT

Excessive catalyst deactivation during the ethanol oxidation reaction (EOR) in an alkaline environment hinders the commercial feasibility of the direct alcohol fuel cell (DAFC). To address this, Pd‐based multimetallic anode electrocatalysts were investigated for their unique adsorption properties and oxophilic nature. The study reveals two primary synergistic mechanisms, demonstrating that the addition of co‐catalysts (Co, Ni, Sn) assists the production of reactive hydroxyl (OH _ad ) species at lower potentials to oxidize the adsorbed CO _ad (the bifunctional effect). In order to reduce the binding strength of CO _ad intermediates, these co‐catalysts alter the electronic structure of Pd (the electronic effect). Multi‐walled carbon nanotubes (MWCNTs) supported PdNi (50:50) exhibit high charge transfer kinetics, CO tolerance, and current retention, whereas all binary catalysts display advanced EOR activity when compared to bare Pd. These findings further highlight the structure‐function relationship achieved by optimizing the geometric arrangement for enhanced EOR performance.