Université de Fribourg

Hybrid magnetic iron oxide nanoparticles with tunable field-directed self-assembly

Malik, Vikash ; Pal, Antara ; Pravaz, Olivier ; Crassous, Jérôme J. ; Granville, Simon ; Grobety, Bernard ; Hirt, Ann M. ; Dietsch, Hervé ; Schurtenberger, Peter

In: Nanoscale, 2017, vol. 9, p. 14405-14413

We describe the synthesis of hybrid magnetic ellipsoidal nanoparticles that consist of a mixture of two different iron oxide phases, hematite (α-Fe2O3) and maghemite (γ-Fe2O3), and characterize their magnetic field-driven self-assembly. We demonstrate that the relative amount of the two phases can be adjusted in a continuous way by varying the reaction time during the synthesis, leading to...

Université de Fribourg

A closer look at the synthesis and formation mechanism of hematite nanocubes

Malik, Vikash ; Grobety, Bernard ; Trappe, Veronique ; Dietsch, Herve ; Schurtenberger, Peter

In: Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2014, vol. 445, p. 21–29

We have synthesized hematite cube-shaped nanoparticles using different synthesis paths to examine the effect of the intermediate product akaganeite (β-FeOOH) on the size and shape of the final hematite particles. Akaganeite spindles and hematite nanocubes are prepared using forced hydrolysis of iron chloride (FeCl₃) salt. We use a combination of transmission electron microscopy (TEM), high...