Induced shape controllability by tailored precursor design in thermal and microwave-assisted synthesis of (Formula presented.) nanoparticles

© 2015, Springer Science+Business Media Dordrecht. Abstract: The shape of magnetite nanoparticles (NPs) synthesized by thermal (T) and microwave (MW) approaches was controlled by an optimized methodology, which consists of a prior and easy modification of the (Formula presented.) terminal position belonging to the iron(III) tris(2,4-pentanedionate) precursor. Round, cuboctahedron, flower-like (Formula presented.) and bow-like (Formula presented.) nanostructures have been synthesized in triethylene glycol media, producing polar dispersible NPs. The (Formula presented.) terminal group was modified from the initial (Formula presented.) to (Formula presented.), and (Formula presented.) respectively, inducing defined and characteristic shapes of the obtained NPs: round, cuboctahedron, flower-like (Formula presented.), and bow-like (Formula presented.), respectively. The two investigated synthetic methodologies, T and MW, produce similar results, except for the precursor containing the aromatic group (Formula presented.), through which cuboctahedron (T) and elongated polycrystalline microwires (MW) were generated. The ensemble of modified ligands has demonstrated to influence the final shape, structure, and composition of the nanocrystals generated. The resulting NPs were studied by high-resolution transmission electron microscopy, X-ray powder diffraction, and thermogravimetric analysis. Data demonstrated a strong relation between the precursor design and the final morphology of the NPs, which could be explained by different precursor–particle interactions during nucleation and crystal growth. The final composition of all nanostructures was the expected (Formula presented.), except for the fluorinated precursor where (Formula presented.) was obtained as the main reaction product. Graphical Abstract: [Figure not available: see fulltext.]