Size control and characterization of wustite (core)/spinel (shell) nanocubes obtained by decomposition of iron oleate complex

Nickel/Iron Oxide Nanocrystals with a Nonequilibrium Phase: Controlling Size, Shape, and Composition

“…From XRD characterization, the dominant crystalline phase was found to be Fe x O; however, the presence of a very broad peak centered at 2θ ∼ 35°indicates the presence of a secondary iron oxide, likely due to deeper oxidation of the Fe x O phase, similar to previous reports on iron oleate decomposition (Supporting Information Figure S7). 49,68,69 Changing the initial metal oleate composition also affected nanoparticle shape, as shown in Figure 7. Nanoparticles synthesized from Ni:Fe 83:17 (t d = 30 min for all samples) precursors appeared as irregularly shaped star-like particles with an average size of 7.3 nm, while nanoparticles synthesized from Ni:Fe 67:33 precursors consisted of a mixture of stars and rounded cubes.…”

Applications of exchange coupled bi-magnetic hard/soft and soft/hard magnetic core/shell nanoparticles

“…Moreover, scanning TEM (STEM) using the so-called high angular annular dark field mode (HAADF) can enhance the elemental contrast as the image intensity, I, scales with near the square of the atomic number, i.e., IZ 1.7 [181]. For instance, Hai et al [187] and Wetterskog et al [188] visualized the core and the shell of Fe 1-x O/Fe 3-δ O 4 nanocubes by comparing DF-TEM images taken using diffracted beams corresponding only to the spinel structure (Fe 3-δ O 4 ) or both the spinel and rock salt structure (Fe 1-x O) (Fig. 2a,b) whereas Pichon et al [189] and Liu et al [190] used STEM-HAADF imaging to highlight the core from the shell (see Fig.2c-d).…”

Synthesis and ageing effect in FeO nanoparticles: Transformation to core–shell FeO/Fe3O4 and their magnetic characterization

“…Although there has been some research on EB in granular materials in the last decades [7][8][9][10][11][12], but the majority of research has focused mainly on thin film systems [13][14][15][16][17]. This is mostly because the spin distribution in granular systems particularly core-shell NPs are essentially more intricate than that of thin films.…”