Controlled aqueous solution synthesis of platinum-palladium alloy nanodendrites with various compositions using amphiphilic triblock copolymers

In a recent study, we demonstrated that Pluronic F127 triblock copolymer plays a critical role in the formation of dendritic Pt nanostructures (L. Wang, Y. Yamauchi, J. Am. Chem. Soc. 2009, 131, 9152-9153). Herein, we expand this concept to produce novel dendritic Pt-Pd alloy nanoparticles. In this paper, a very simple, one-step and efficient route is proposed to directly produce dendritic Pt-Pd alloy nanoparticles with high surface area in high yield, which is carried out simply by stirring an aqueous solution that contains K ₂PtCl₄ and Na₂PdCl₄ binary precursors in the presence of Pluronic F127 block copolymer and ascorbic acid at room temperature within 30 min without the need for any template, seed-mediated growth, or additive. By simply changing the compositional ratios of the Pt and Pd sources in the precursor solutions, Pt-Pd nanodendrites with various compositions can be easily produced. Because of its unique simplicity, the proposed approach can be considered as a powerful strategy for producing Pt-Pd alloy nanoparticles with unique nanoarchitectures for commercial devices.