Shape Control of Platinum Nanoparticles

Abstract

The synthesis of shape controlled platinum nanoparticles has been investigated through an organometallic approach starting from the complex Pt2(dba)3 and using a long alkyl chain amine, hexadecylamine (HDA), as stabilizer. The influence of the experimental parameters (reactive gas and solvent nature, stabilizer/metal ratio, reactants concentration, temperature) on the shape of the Pt nanoparticles has been studied. Various shaped platinum nanostructures such as isolated nanoparticles, dendrites or crystalline nanowires were obtained, depending on the reaction conditions. This method takes profit of the mild conditions of chemistry in solution and allows obtaining regular nanostructures, most of them being homogeneous in shape as well as in size (isolated nanoparticles) or diameter/length (nanowires). Transmission electron microscopy and wide‐angle X‐ray scattering were used as characterization techniques. Beside the Knight‐shift effect of platinum, NMR solution investigations clearly evidenced the coordination of the amine at the Pt particles surface and its mobility. This mobility, increased when H2 is used as reactive gas for the precursor decomposition, favors the particles coalescence into nanowires. This phenomenon is also favored by the “soft” template character of the amine in particular in toluene solution.

Controlled metal nanostructures: Fertile ground for coordination chemists

“…Au [119], Ru [38], Re [47] Pd [120], Pt [121],Co [22], Ag [78] or Cu [114] NPs. Similarly, isonitriles are used on Pd [122], [123], Ag or Au NPs [124], [125], [126], nitriles on Pt-Fe alloy NPs [127].…”

Nanostructured Electrocatalyst Synthesis: Fundamental and Methods

“…Electrochemical and electroless depositions, chemical polymerization, sol-gel deposition, and chemical vapor deposition have been presented as major template synthetic strategies. To date a variety of templates have been successfully demonstrated for the formation of nanomaterials including self-assembled organic surfactants/block copolymers, channels in porous materials, step edges on solid substrates, and the existing nanostructures [110][111][112][113][114][115][116][117][118][119]. Generally, these templates are classified into two types namely, hard templates and soft templates, where the hard templates are involved physically and need to be removed selectively after the synthesis of desired nanostructures.…”

Electrochemical characterization of platinum nanoparticles stabilized by amines

“…They also mentioned that these materials can be obtained free of possible surface contamination. Recently, the same authors have reported interesting results on the obtention of Pt nanoparticles from Pt 2 (dba) 3 as metallic precursor and hexadecylamine as stabilizer [9]. However, up to now, synthesis of Pt nanoparticles stabilized by amines from organometallic precursors for electrocatalysts is not found to best of scientist knowledge.…”