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Self-Assembly of Pluronic F127-Silica Spherical Core-Shell Nanoparticles in Cubic Close-Packed Structures.

ABSTRACT: A new ordered mesoporous silica material (COK-19) with cubic symmetry is synthesized by silicate polycondensation in a citric acid/citrate buffered micellar solution of Pluronic F127 triblock copolymer near neutral pH. SAXS, nitrogen adsorption, TEM, and electron tomography reveal the final material has a cubic close packed symmetry (Fm3?m) with isolated spherical mesopores interconnected through micropores. Heating of the synthesis medium from room temperature to 70 °C results in a mesopore size increase from 7.0 to 11.2 nm. Stepwise addition of the silicate source allows isolation of a sequence of intermediates that upon characterization with small-angle X-ray scattering uncovers the formation process via formation and aggregation of individual silica-covered Pluronic micelles.

SUBMITTER: Kerkhofs S

PROVIDER: S-EPMC4898863 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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Self-Assembly of Pluronic F127-Silica Spherical Core-Shell Nanoparticles in Cubic Close-Packed Structures.

Kerkhofs Stef S Willhammar Tom T Van Den Noortgate Heleen H Kirschhock Christine E A CE Breynaert Eric E Van Tendeloo Gustaaf G Bals Sara S Martens Johan A JA

Chemistry of materials : a publication of the American Chemical Society 20150724 15

A new ordered mesoporous silica material (COK-19) with cubic symmetry is synthesized by silicate polycondensation in a citric acid/citrate buffered micellar solution of Pluronic F127 triblock copolymer near neutral pH. SAXS, nitrogen adsorption, TEM, and electron tomography reveal the final material has a cubic close packed symmetry (<i>Fm</i>3̅<i>m</i>) with isolated spherical mesopores interconnected through micropores. Heating of the synthesis medium from room temperature to 70 °C results in ...[more]

PMID: 27293311

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