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Improved Solvothermal Synthesis of γ-Fe₂O₃ Magnetic Nanoparticles for SiO₂ Coating.

ABSTRACT: Monodisperse magnetic γ-Fe₂O₃ nanoparticles (MNPs) were prepared by a simple, improved, one-pot solvothermal synthesis using SDS and PEG 6000 as double capping reagents. This double protecting layer afforded better MNP uniformity (Z average 257 ± 11.12 nm, PDI = 0.18) and colloidal stability. Materials were characterized by DLS, SEM, TEM, XPS, and XRD. The use of these MNPs in the synthesis of core-shell structures with uniform and tunable silica coatings was demonstrated, as silica coated MNPs are important for use in a range of applications, including magnetic separation and catalysis and as platforms for templated nanogel synthesis.

SUBMITTER: Mahajan R

PROVIDER: S-EPMC8398533 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Improved Solvothermal Synthesis of γ-Fe2O3 Magnetic Nanoparticles for SiO2 Coating.

Mahajan Rashmi R Suriyanarayanan Subramanian S Nicholls Ian A IA

Nanomaterials (Basel, Switzerland) 20210723 8

Monodisperse magnetic γ-Fe2O3 nanoparticles (MNPs) were prepared by a simple, improved, one-pot solvothermal synthesis using SDS and PEG 6000 as double capping reagents. This double protecting layer afforded better MNP uniformity (Z average 257 ± 11.12 nm, PDI = 0.18) and colloidal stability. Materials were characterized by DLS, SEM, TEM, XPS, and XRD. The use of these MNPs in the synthesis of core-shell structures with uniform and tunable silica coatings was demonstrated, ...[more]

PMID: 34443719

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