Effects of silica coating on the magnetic properties of magnetite nanoparticles
Source abstract
Abstract
Abstract Research on magnetic nanoparticles of magnetite (MNPs) has intensified because it can be coated with different materials leading to diverse properties. In this work, MNPs and silica coated MNPs were synthesized by co-precipitation of Fe(III) and Fe(II) precursors, different proportions of tetraethylorthosilicate (TEOS), and scales showing high reproducibility and proximity of crystalline domains. Spectra of FT-IR exhibited the formation of Si OH Fe bonds. TEM images revealed that most of the MNPs were spherical with a fair distribution of encapsulated nanoparticles. Magnetization increased as the amount of silica coating increases. Silica coating did not modify the shape and structure of the MNPs cylindrical mesoporous open in the extremities. Adsorption of pyridine on the MNPs demonstrated the presence of hydrogen bonding, Lewis and Bronsted sites. For MNPs coated with silica, there was a neutralization of the Bronsted leading to weaker Lewis (coordinatively unsaturated iron) and hydrogen bonding sites (silanol groups).
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Magnetic Properties and Synthesis of Ferrites · Iron oxide chemistry and applications · Advancements in Battery Materials
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
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