NixPt1−x is the missing link in the series of magnetic alloy particles. We report here on the first high‐quality synthesis of this nanomaterial. Although the chemistry of the Fe, Co, and Ni compounds is usually similar, distinctive differences are found in the nucleation, growth, and shape control of the respective nanoparticles, and first magnetic measurements are presented. The image shows star‐shaped agglomerates of nanoparticles.

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The formation of monodisperse, tunable sized, alloyed nanoparticles of Ni, Co, or Fe with Pt and pure Pt nanoparticles attached to carbon nanotubes has been investigated. Following homogeneous nucleation, nanoparticles attach directly to non-functionalized singlewall and multiwall carbon nanotubes during nanoparticle synthesis as a function of ligand nature and the nanoparticle work function. These ligands do not only provide a way to tune the chemical composition, size and shape of the nanoparticles but also control a strong reversible interaction with carbon nanotubes and permit controlling the nanoparticle coverage. Raman spectroscopy reveals that the sp2 hybridization of the carbon lattice is not modified by the attachment. In order to better understand the interaction between the directly attached nanoparticles and the non-functionalized carbon nanotubes we employed first-principles calculations on model systems of small Pt clusters and both zig-zag and armchair singlewall carbon nanotubes. The detailed comprehension of such systems is of major importance since they find applications in catalysis and energy storage.Composites of metallic nanoparticles (NPs) and carbon nanotubes (CNTs) exhibit high catalytic activity for various chemical reactions [1][2][3][4][5][6] and have also been explored for hydrogen storage applications [7]. Recent reports include platinum [6,8,9] [19,20] and catalytic properties [21][22][23]. Beyond that, 1D alignment of NPs enables to modify the saturation magnetization and coercitivity through magnetostatic coupling [24][25][26]. A convenient way for 1D alignment is the attachment of NPs to CNTs, which is usually achieved by electrochemical deposition [27,28], the reduction of metallic salts in the presence of functionalized CNTs [15,29], or chemical vapor deposition [10], among others [30]. On the other hand, concerning the NP synthesis, the organometallic synthesis route provides nanocrystalline alloyed materials with precise size control and tunable composition in several systems [20,31,32]. Here, we report on the synthesis of alloyed N i x P t 1−x [20], Co x P t 1−x and F e x P t 1−x [32] NPs as well as pure P t [33] NPs and their attachment to non-functionalized singlewall (SWCNTs), multiwall carbon nanotubes (MWCNTs) and glassy carbon by their simple integration in the organometallic synthesis. The experimental procedure involves only a single synthetic step, whereby the crucial parameter for attachment was found in the correct balance of the ligands oleylamine (OA) and oleic acid (Oac).

Nanocomposite materials based on highly stable encapsulated superparamagnetic iron oxide nanocrystals (SPIONs) were synthesized and characterized by scattering methods and transmission electron microscopy (TEM). The combination of advanced synthesis and encapsulation techniques using different diblock copolymers and the thiol-ene click reaction for cross-linking the polymeric shell results in uniform hybrid SPIONs homogeneously dispersed in a poly(ethylene oxide) matrix. Small-angle X-ray scattering and TEM investigations demonstrate the presence of mostly single particles and a negligible amount of dyads. Consequently, an efficient control over the encapsulation and synthetic conditions is of paramount importance to minimize the fraction of agglomerates and to obtain uniform hybrid nanomaterials.

Nanocrystal encapsulation with highly stable polymer shell for nanocomposite synthesis and detailed characterization with small angle scattering and electron microscopy.