Ligand-Free Pt-Ln Nanoclusters Synthesized by Femtosecond Lasers for Electrocatalytic Methanol Oxidation

Methanol oxidation reaction (MOR) is critical for direct methanol fuel cells (DMFCs), but designing cost-effective Pt-based catalysts with high catalytic activity remains challenging. The study synthesizes lanthanide-doped Pt nanoclusters via femtosecond laser ablation, with PtLa clusters achieving a mass activity of up to 17.50 A mg Pt −1 . Characterization shows these metastable PtLa nanoclusters feature clean surfaces and uniform La distribution within Pt nanocrystal frameworks. Comprehensive in situ/operando techniques, including attenuated total reflectance-surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS), ambient pressure X-ray photoelectron spectroscopy (APXPS), and X-ray absorption spectroscopy (XAS), demonstrate that La incorporation markedly enhances both OH − adsorption and the central role of HCOO − as the primary reaction intermediate during MOR. Ultraviolet photoelectron spectroscopy (UPS) and density functional theory (DFT) calculations indicate La doping elevates the Pt d-band center, strengthening intermediate adsorption and reducing kinetic barriers. The oxygenophilic nature of La enhances local OH − coverage near active sites, facilitating the activation of reaction intermediates and accelerating the turnover rate at electrolyte/electrode interface. The study provides a facile and effective strategy for synthesizing conventionally difficult-to-synthesize catalysts using femtosecond laser technology, paving the way for the controlled preparation of rare earth alloys and applications in large-scale deployment of DMFCs and beyond.