Controlled Synthesis of Gold Nanoparticles in Copolymers Nanomolds by X-ray Radiolysis - CNRS - Centre national de la recherche scientifique Accéder directement au contenu
Article Dans Une Revue Langmuir Année : 2020

Controlled Synthesis of Gold Nanoparticles in Copolymers Nanomolds by X-ray Radiolysis

Résumé

We show by X-ray and neutron small-angle scattering that gold nanoparticles with controlled sizes and morphologies can be obtained by the metallic reduction of AuCl4– ions trapped in 3D organic molds by X-ray radiolysis. The molds are spherical frozen micelles of polystyrene-b-poly(dimethylaminoethyl methacrylate) (PS-b-PDMAEMA) block copolymer in acidic aqueous solution with a PS spherical core surrounded by a corona of PDMAEMA chains in good solvent. The behavior of micelles is controlled by the [AuCl4–]/[DMAEMA] ratio RAuCl4–/DMAEMA. At low gold concentration, AuCl4– ions condense on the positively charged DMAEMA moieties without changing the behavior of the PDMAEMA chains. At intermediate gold concentration, the ions induce a progressive contraction of the corona’s chains and dehydration of micelles. At large gold concentration, the corona becomes a fully dry phase loaded with gold ions, which induces micelle aggregation. Radiolysis of the solution by an intense X-ray beam produces different types of gold nanoparticles with respect to RAuCl4–/DMAEMA and irradiation time. At RAuCl4–/DMAEMA = 0.033, irradiation produces in the first step gold clusters in the micelle corona which in the second step merge to form nanoparticles of a similar size to that of the micelle. Conversely, at RAuCl4–/DMAEMA = 0.33, micelles do not operate as templates but only as nucleation zones and large nanoparticles grow outside the micelles.
Fichier non déposé

Dates et versions

hal-03097716 , version 1 (05-01-2021)

Identifiants

Citer

Louis Bondaz, Philippe Fontaine, François Muller, Nadège Pantoustier, Patrick Perrin, et al.. Controlled Synthesis of Gold Nanoparticles in Copolymers Nanomolds by X-ray Radiolysis. Langmuir, 2020, 36 (22), pp.6132-6144. ⟨10.1021/acs.langmuir.0c00554⟩. ⟨hal-03097716⟩
64 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More