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Electrochemical atomic layer deposition was used to form bimetallic (BiPd, CuPd) and trimetallic (CuBiPd) thin films via surface‐confined reactions. Pd thin films were characterized by cyclic voltammetry, scanning electron microscopy (SEM) and the alloy formation with preferred Au/Pd(111) orientation was confirmed by XRD. AFM revealed uniform grain distribution, with 3D islands growing on CuBiPd. EDX verified the presence of all deposited elements. Compared to other prepared catalysts, CuBiPd catalyst showed higher activity and stability towards the ethanol oxidation reaction (EOR), as confirmed by the peak current and onset potential trends, respectively: CuBiPd (1.35 mA, −0.450 V)>CuPd (0.6016 mA, −0.442 V)>BiPd (0.275 mA, −0.384 V)>Pd (0.186 mA, −0.350 V). The EOR current on CuBiPd improved by 2.5 folds relative to Pd. The results show that CuBiPd electrocatalyst is a promising material for EOR with enhanced catalytic properties for direct ethanol fuel cell [ABSTRACT FROM AUTHOR]

• Electrosynthesis of thin film Pd based catalyst using E-ALD technique. • PdIr thin films were deposited via SLRR with Cu UPD as a sacrificial metal. • Thin films were deposited on Au through alternation of 15 SLRR cycles. • PdIr exhibits high current density towards the oxidation of ethanol than Pd. • Incorporation of Ir enhanced conductivity and electron transfer kinetics of Pd. This work reports Pd and PdIr thin films electrodeposition via surface limited redox replacement reaction using electrochemical atomic layer deposition technique. Cyclic voltammetry (CV) showed Pd and PdIr voltammetric signatures confirming the successful utilization of Cu as sacrificial metal for Pd and Ir ions. The resulting deposits were further characterized using XRD, EDS, XPS, SEM and AFM, confirming their structural morphology and surface roughness. The catalytic activity of the thin films towards the oxidation of ethanol was determined using CV. PdIr showed a more negative onset potential and higher current (−0.423 V; 0.664 mA) than Pd (−0.402 V; 0.494 mA) thin film, indicating a more catalytic behavior. Further, PdIr showed a higher if/ib ratio of 1.094 than Pd (if/ib = 0.94) indicating higher tolerance to poisoning by ethanol intermediates than Pd. Moreover, chronoamperometry (CA) confirmed that the addition of Ir to Pd improves the stability of the PdIr film. The resultant behaviour was also confirmed by EI spectroscopy with smaller Rct = 0.23 (kΩ) for PdIr than that of Pd; Rct = 14.8 (kΩ) when. Subjected at a fixed potential of −0.2 V. The higher catalytic activity of PdIr towards EOR makes it a promising candidate as electrocatalyst for alkaline direct ethanol fuel cell (DEFCs) than Pd. [ABSTRACT FROM AUTHOR]