Dataset for the article: Electrochemical and surface science data for stabilized Pt-Pd-Co catalysts for methanol oxidation

Dataset Description This dataset contains raw and processed data obtained from the physicochemical characterization of Pt-Pd-Co-based electrocatalysts using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS) and X-ray photoelectron spectroscopy (XPS). The data were generated to evaluate the elemental composition, spatial elemental distribution, and surface chemical states of the synthesized electrocatalysts. SEM-EDS and Elemental Mapping Data SEM-EDS analyses were performed after preparing conductive and mechanically stable samples on aluminum stubs coated with conductive silver paint (TED PELLA, INC.). A homogeneous amount of each electrocatalyst powder was deposited onto the conductive coating. Elemental composition data were acquired in backscattered electron (BSE) mode using Bruker analytical software. For each sample, at least five independent regions were analyzed to ensure representative elemental quantification and to assess compositional homogeneity. Elemental mapping datasets were generated using the same prepared samples. A representative area of each sample was selected, and elemental distribution maps were collected in BSE mode with an acquisition time of 1 h per sample. These data provide spatial information regarding the distribution of platinum, palladium, cobalt, oxygen, carbon, and other detected elements across the catalyst surface. The EDS section of the dataset includes: • Quantitative elemental compositions obtained from multiple measurement zones. • Processed elemental maps showing the spatial distribution of detected elements. • Metadata associated with acquisition conditions and analytical parameters. XPS Data XPS measurements were conducted to determine both the surface elemental composition and the chemical states of the constituent elements. Initially, low-resolution survey spectra were collected to identify all detectable elements present on the catalyst surface and verify consistency with the expected catalyst stoichiometry. Subsequently, high-resolution spectra were acquired for the principal elements of interest, including C 1s, Pt 4f, Pd 3d, Co 2p, and O 1s. To ensure reliable interpretation of chemical states, each high-resolution spectrum was processed through Gaussian-Lorentzian peak deconvolution using a Shirley background correction. Prior to fitting, all spectra were corrected for charging effects using the C 1s reference peak at 284.5 eV. Peak assignments and oxidation-state identification were performed according to the Handbook of X-ray Photoelectron Spectroscopy, relevant peer-reviewed literature, and the NIST X-ray Photoelectron Spectroscopy Database Version 5 (Lee et al., 2024). The XPS section of the dataset includes: • High-resolution spectra for C 1s, Pt 4f, Pd 3d, Co 2p, and O 1s. • Charge-corrected spectra. • Gaussian-Lorentzian fitting outputs and deconvolution parameters. • Binding energy values and peak assignments.