Surface‐Roughened Pt‐Decorated Pd Nanoparticles as Efficient Electrocatalysts for Direct Alcohol Fuel Cells

다국어 초록 (Multilingual Abstract)

Platinum‐decorated Pd nanoparticles (NPs) of Pd100–xPtx (x = 30, 40 and 50) are synthesised by galvanic replacement of Ag by Pt using a Pd@Ag core–shell structure as a template. The Pd@Ag core–shell material is prepared by chemical reduction of Ag+ over Pd NPs, with further Ag being galvanically replaced by Pt to form Pd100–xPtx NPs. The Pd100–xPtx NPs are characterised using optical absorption spectroscopy with surface plasmon resonance (SPR), transmission electron microscopy (TEM) and high resolution TEM (HRTEM). The NPs are adsorbed onto vulcan carbon (Pd100–xPtx/C) for further characterisation and electrochemical studies. The materials are characterised using powder X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS) and cyclic voltammetry (CV) studies. The CV studies indicate the absence of silver in the synthesised materials. The electrochemical oxidation of methanol and ethanol are carried out by cyclic voltammetry studies. The results show that Pd100–xPtx/C materials are good catalysts for methanol oxidation reactions (MORs) and ethanol oxidation reactions (EORs), with lower oxidation potentials and higher mass activities than commercial Pt/C catalysts. Among these materials, Pd50Pt50/C has a methanol oxidation potential of 0.18 V, with good mass activity, and the Pd70Pt30/C material is an efficient EOR catalyst, with higher mass activity than commercial Pt/C catalysts.
Surface‐enriched platinum‐decorated Pd NPs prepared by a Pd–Ag template, followed by a galvanic replacement reaction, act as a highly efficient electrocatalyst, with a lower oxidation potential than commercial Pt/C catalysts for methanol and ethanol oxidation reactions.