콘텐츠로 건너뛰기
Merck
  • Ligand-induced fate of embryonic species in the shape-controlled synthesis of rhodium nanoparticles.

Ligand-induced fate of embryonic species in the shape-controlled synthesis of rhodium nanoparticles.

ACS nano (2015-01-30)
Adam J Biacchi, Raymond E Schaak
초록

The shapes of noble metal nanoparticles directly impact their properties and applications, including in catalysis and plasmonics, and it is therefore important to understand how multiple distinct morphologies can be controllably synthesized. Solution routes offer powerful capabilities for shape-controlled nanoparticle synthesis, but the earliest stages of the reaction are difficult to interrogate experimentally and much remains unknown about how metal nanoparticle morphologies emerge and evolve. Here, we use a well-established polyol process to synthesize uniform rhodium nanoparticle cubes, icosahedra, and triangular plates using bromide, trifluoroacetate, and chloride ligands, respectively. In all of these systems, we identified rhodium clusters with diameters of 1-2 nm that form early in the reactions. The colloidally stable metal cluster intermediates served as a stock solution of embryonic species that could be transformed predictably into each type of nanoparticle morphology. The anionic ligands that were added to the embryonic species determined their eventual fate, e.g., the morphologies into which they would ultimately evolve. Extensive high-resolution transmission electron microscopy experiments revealed that the growth pathway-monomer addition, coalescence, or a combination of the two-was different for each of the morphologies, and was likely controlled by the interactions of each specific anionic adsorbate with the embryonic species. Similar phenomena were observed for related palladium and platinum nanoparticle systems. These studies provide important insights into how noble metal nanoparticles nucleate, the pathways by which they grow into several distinct morphologies, and the imperative role of the anonic ligand in controlling which route predominates in a particular system.

MATERIALS
제품 번호
브랜드
제품 설명

Supelco
Diethylene glycol, Pharmaceutical Secondary Standard; Certified Reference Material
Supelco
Ethylene glycol, Pharmaceutical Secondary Standard; Certified Reference Material
Supelco
Water, suitable for ion chromatography
Sigma-Aldrich
Water, BioPerformance Certified
Supelco
Density Standard 998 kg/m3, H&D Fitzgerald Ltd. Quality
Supelco
Water, ACS reagent, for ultratrace analysis
Supelco
Ethylene glycol solution, NMR reference standard, 80% in DMSO-d6 (99.9 atom % D), NMR tube size 5 mm × 8 in.
USP
Dehydrated Alcohol, United States Pharmacopeia (USP) Reference Standard
Sigma-Aldrich
Diethylene glycol, ReagentPlus®, 99%
Sigma-Aldrich
Water, deuterium-depleted, ≤1 ppm (Deuterium oxide)
Supelco
Ethanol solution, certified reference material, 2000 μg/mL in methanol
Sigma-Aldrich
Water, for cell biology, sterile ultrafiltered
Sigma-Aldrich
Ethylene glycol, BioUltra, ≥99.5% (GC)
Sigma-Aldrich
Diethylene glycol, puriss. p.a., ≥99.0% (GC), colorless
Supelco
Water, for HPCE, for luminescence, suitable for UV/Vis spectroscopy
Sigma-Aldrich
Diethylene glycol, BioUltra, ≥99.0% (GC)
Sigma-Aldrich
Water, tested according to Ph. Eur.
Supelco
Diethylene glycol, analytical standard
Sigma-Aldrich
Water, for molecular biology, sterile filtered
Sigma-Aldrich
Sodium bromide, ≥99.99% trace metals basis
Sigma-Aldrich
Water, for embryo transfer, sterile-filtered, BioXtra, suitable for mouse embryo cell culture
Sigma-Aldrich
Water, PCR Reagent
Sigma-Aldrich
Sodium bromide, BioXtra, ≥99.0%
USP
Diethylene glycol, United States Pharmacopeia (USP) Reference Standard
USP
Ethylene glycol, United States Pharmacopeia (USP) Reference Standard
Sigma-Aldrich
Water, Nuclease-Free Water, for Molecular Biology
Sigma-Aldrich
Ethylene glycol, anhydrous, 99.8%
Supelco
Water, for TOC analysis
Sigma-Aldrich
Water, sterile-filtered, BioReagent, suitable for cell culture
Sigma-Aldrich
Water, suitable for HPLC