Synthesis and Phase Transfer of Monodisperse Iron Oxide (Fe3O4) Nanocubes

Abstract

Cube-shaped magnetic iron oxide nanoparticles were synthesised and studied with the aim to achieve superior magnetic properties. This study describes a straightforward and simple synthesis method for preparing monodisperse 11-14-nm superparamagnetic iron oxide nanocubes via an 'effective monomer' growth mechanism. The as-synthesised nanoparticles are insoluble in water. However, substitution of the non-polar ligands of the particles using a new method that involved an ionic compound generated colloidally stable and water dispersible cube-shaped particles with a very small hydrodynamic diameter. The cubes displayed superior magnetic properties over spherical particles.

Unravelling the Surface Chemistry of Metal Oxide Nanocrystals, the Role of Acids and Bases

“…The observation that at least for HfO2 and ZrO2, the NC surface provides a medium where acid base reactions can proceed in nonpolar solvents extends considerably the possibility for ligand exchange reactions with these MONCs. Instead of only exchanging the anionic species -as is common practice with metal sulfide, selenide or telluride NCs 23,24,47 -the MONC surface can be modified by exchanging the proton for other cations.…”

Selective assembly of Au-Fe3O4 nanoparticle hetero-dimers

“…The original cetyltrimethylammonium bromide (CTAB) ligands were exchanged against 3-mercaptopropianic acid (3-MPA) using a published method [ 32 ]. Cube shaped Fe 3 O 4 nanoparticles with an edge length of approximately 11 nm were synthesised through thermal decomposition of iron oleate, followed by surface ligand exchange against oxalic acid as reported previously [ 17 ]. This resulted in two different types of nanoparticles, which were both carboxylated on their surface (Fig.…”

“…Interestingly, some analytical methods are based on the dimerisation or controlled coagulation of individual nanoparticles [ 13 , 14 ]. It is known that the properties and performance of nanoparticles are strongly affected by the shape, size, crystalline structure, as well as the monodispersity of the materials [ 15 – 17 ]. Although it is possible to tune the properties of nanoparticles by modifying these attributes, there are limits in engineering chemical and physical properties.…”

Rapid microwave assisted synthesis of nearly monodisperse aqueous CuInS2/ZnS nanocrystals

“…16 There are many strategies by which hydrophobic NCs can be made hydrophilic such as silica shell capping, 23 ligand exchange [24][25][26] and amphiphilic polymer coatings. 16 There are many strategies by which hydrophobic NCs can be made hydrophilic such as silica shell capping, 23 ligand exchange [24][25][26] and amphiphilic polymer coatings.…”