Ligand-free synthesis of PtPdCu ternary nanostructures with controllable morphologies for efficient methanol oxidation

Abstract

Nanocatalysts prepared by the ligand-free synthesis method generally exhibit superior catalytic activity due to the absence of ligand interference. Nevertheless, the morphologies of nanocatalysts and the components, particularly for ternary nanoalloys, in ligand-free synthesis are challenging to regulate. In this work, we successfully fabricated a range of ligand-free PtPdCu ternary nanocatalysts with controlled morphologies and sizes employing the Cu2O template sacrificial method while precisely adjusting the components of Pt, Pd, and Cu. The synthesized PtPdCu ternary nanocatalysts have two types: PtPdCu ternary nanodendrites with varied sizes, and PtPdCu ternary nanoboxes with different arm thicknesses. In all the synthesized PtPdCu nanocatalysts, the molar ratio of Pt/Pd is maintained at 1/3, and the proportion of Cu in the ultimate nanocatalysts is positively correlated with the proportion of the initial Cu2O. Due to the synergistic ternary composition, distinct morphology, and unique surface electronic configuration of PtPdCu ternary nanocatalysts, they show significantly enhanced activity and stability for the methanol oxidation reaction. This paper provides novel insights into the ligand-free synthesis of morphology-regulated and multi-component-controlled nanocatalysts, which can be used for high-performance catalysis.