Precise Control of the Pt Nanoparticle Size by Seeded Growth Using EO13PO30EO13 Triblock Copolymers as Protective Agents

Abstract

Here, we report an efficient way to produce homogeneous Pt nanoparticles within a well-defined size range (3.5−6.6 nm) as a result of the seeded growth procedure using Pluronic L64 polymer capping agent. First, small seeds (3.5 nm) were prepared by the reduction of H₂PtCl₆·6H₂O in water with NaBH₄ in the presence of the capping poly(ethylene oxide)₁₃−poly(propylene oxide)₃₀−poly(ethylene oxide)₁₃ triblock copolymer at room temperature. Additional anionic Pt salt was then introduced under flowing H₂ to obtain larger nanoparticles.