Abstract
The commercialization of direct ethanol fuel cells (DEFCs) is hindered by platinum dependency, catalyst degradation, and high costs. This work addresses these challenges by developing carbon-supported trimetallic PdAuM/C (M = Rh, Ir, Ag) electrocatalysts for the ethanol oxidation reaction (EOR). Through a controlled synthesis protocol, PdAuM/C nanoparticles (3.1–6.7 nm) with alloyed structures were characterized by XRD, TEM, EDX, and XPS. Electrochemical analyses (CV, CA, EIS) in alkaline media revealed unprecedented EOR activity: PdAuRh/C achieved a peak current density of 10,500 mA·mg⁻¹Pd and onset potential of − 680 mV vs. NHE—5.8× higher current and 195 mV lower overpotential than monometallic Pd/C (1,800 mA·mg⁻¹Pd, − 485 mV). PdAuIr/C and PdAuAg/C also outperformed Pd/C, though PdAuAg exhibited a typical dual oxidation peaks. The synergistic electronic effects in PdAuRh/C minimized CO poisoning and maximized active sites, positioning it as a sustainable, high-performance alternative to Pt-based catalysts for DEFCs.
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The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.
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Acknowledgements
Ahmed Elsheikh is grateful for the financial support of the Newton-Mosharafa Fund (Reference no. NMJ8/15) for his Ph.D. studies.
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**A. ElSheikh** : Conceptualization, Data Curation, Methodology, Funding Acquisition, & Project administration. **H. AlSogheir** : Investigation and Manuscript Composition. **H. Mousa** : Contributed to drafting and reviewing the manuscript. C. Zhu: Data Analysis, assessment, and manuscript review . **J. McGregor** : Conceptualization, Methodology, Result analysis, and Funding Acquisition.
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ElSheikh, A., Alsoghier, H.M., Mousa, H.M. et al. Synthesis of carbon-supported multimetallic palladium-based electrocatalysts for direct ethanol fuel cells (DEFCs). Sci Rep (2026). https://doi.org/10.1038/s41598-026-35821-x
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DOI: https://doi.org/10.1038/s41598-026-35821-x
