Rapid hot-injection as a tool for control of magnetic nanoparticle size and morphology

The rapid hot-injection (HI) technique was employed to synthesize magnetic nanoparticles with well-defined morphology (octahedrons, cubes, and star-like). It was shown that the proposed synthetic approach could be an alternative for the heat-up and flow hot-injection routes. Instant injection of the precursor to the hot reaction mixture (solvent(s) and additives) at high temperatures promotes fast nucleation and particle directional growth towards specific morphologies. We state that the use of saturated hydrocarbon namely hexadecane (sHD) as a new co-solvent affects the activity coefficient of monomers, forces shape-controllable growth, and allows downsizing of particles. We have shown that the rapid hot-injection route can be extended for other ferrites as well (ZnFe2O4, CoFe2O4, NiFe2O4, and MnFe2O4) which has not been done previously through the HI process before.

Automated summary

The rapid hot-injection technique was used to synthesize magnetic nanoparticles with well-defined morphology, promoting particle growth and directional shaping. The use of hexadecane as a co-solvent affects monomer activity coefficient, forces shape-controllable growth, and enables particle downsizing. This approach can also be extended to other ferrites, which has not been previously achieved through the hot-injection process.