Pd-based metallic nanosheets with advanced physicochemical properties have been widely prepared and employed in various electrocatalytic reactions. However, few concerns were focused on their multiple performances in different electrocatalysis. Here, highly curved and ultrathin PdNiRu nanosheets (NSs) are developed by facile wet-chemistry strategy and exhibit excellent electrocatalytic performance toward both oxygen reduction reaction (ORR) and ethylene glycol oxidation reaction (EGOR). Owing to the synergistically structural (e.g., ultrathin, curved, defects/steps-rich) and compositional (ternary alloy) advantages, PdNiRu NSs exhibited enhanced ORR and EGOR specific/mass activities and better stability/durability than control electrocatalysts. The specific activity (5.52 mA·cm⁻²) and mass activity (1.13 A·mg_Pd⁻¹) of the PdNiRu NSs in ORR are 4.8 and 3.4 times as the ones of commercial Pt/C, respectively. The mass activity of PdNiRu NSs (3.86 A·mg_Pd⁻¹) in EGOR is 2.6 times as commercial Pd/C (1.51 A·mg_Pd⁻¹). This study is helpful for the development of desired electrocatalysts with multi-functional application in practical fuel cells.

Coupling the bi-functional mechanism with compressive lattice strain might be an effective way to boost the electrocatalysis of platinum (Pt)-based nanoparticles for methanol oxidation reaction (MOR). This strategy weakens the chemisorption of poisoning CO-like intermediates generated during MOR on the active Pt sites by lowering their d-band center. In this context, we herein report the synthesis of ternary copper-tungsten-platinum (CuWPt) nanoalloys with light doping of W element by simply co-reducing their precursors at elevated temperature. In this ternary alloy system, the presence of only small amount of W element not only weakens the chemisorption of CO-like intermediates by lowering the Pt d-band center through compressive lattice strain, but also cleans the active Pt sites by "hydrogen spillover effect", endowing the as-prepared CuWPt nanoalloys at an appropriate Cu/W/Pt ratio with good activity for MOR. In specific, the ternary CuWPt alloy nanoparticles at a Cu/W/Pt molar ratio of 21/4/75 show a specific activity of 2.5 mA·cm⁻² and a mass activity of 2.11 A·mg⁻¹ with a better durability, outperforming those ternary CuWPt alloy nanoparticles at other Cu/W/Pt ratios, binary CuPt alloys and commercial Pt/C catalyst as well as a large number of reported Pt-based electrocatalysts. In addition, a single direct methanol fuel cell (DMFC) assembled using ternary CuWPt nanoalloys as anodic catalysts shows a power density of 24.3 mW·cm⁻² and an open-circle voltage of 0.6 V, also much higher than those of the single DMFC assembled from commercial Pt/C catalysts.