Insertion of Palladium Nanoparticles on Carbon Dots for Enhanced Ethanol Oxidation Performance in Alkaline Media

This study reports the hydrothermal synthesis of PdX/CDs nanocomposites with varying palladium contents, confirmed by inductively coupled plasma mass spectrometry (ICP–MS) analysis, and their comprehensive physicochemical and electrochemical characterization for ethanol oxidation reaction (EOR) in alkaline media. The carbon dots (CDs), synthesized from D‐galactose and L‐histidine, serve as a porous, conductive support that enhances Pd nanoparticle dispersion and electronic conductivity. Among the catalysts tested, the Pd2/CDs nanocomposite exhibited superior performance, delivering a high anodic peak current density of 26 mA cm ⁻² , a low charge transfer resistance of 450 Ω, and a small Tafel slope of 61.97 mV dec ⁻¹ . Electrochemical stability was demonstrated through chronoamperometric tests, highlighting the catalyst's durability under alkaline conditions. Enhanced activity is attributed to the increased electrochemically active surface area, suppressed nanoparticle agglomeration, and efficient charge transport facilitated by the CDs. These findings position Pd2/CDs as a promising, cost‐effective electrocatalyst alternative to platinum for direct ethanol fuel cells (DEFCs), addressing key challenges such as catalyst poisoning and slow kinetics while leveraging the advantageous structural and electronic properties of both Pd nanoparticles and carbon dots.