Under the right process conditions, nanoparticles can cluster together to form defined, dispersed structures, which be termed supraparticles. Controlling size, shape, and morphology of such entities is a central step in various fields science technology, ranging from colloid chemistry soft matter physics powder technology pharmaceutical food sciences. These diverse scientific communities have been investigating formation processes structure/property relations supraparticles under completely...

Ferrofluids of superparamagnetic Fe₃O₄ nanoparticles with “patchy” silica shell are stable over a wide pH range and in physiological solutions.

A smart optical composite material with dynamic isotropic and anisotropic properties by combination of luminescence high reflectivity was developed. This enables switching between angle-dependent changing the applied wavelength light. The is formed as core/shell particles coating superparamagnetic iron oxide-silica microrods a layer luminescent metal-organic framework (MOF) 3∞[Eu2(BDC)3]·2DMF·2H2O (BDC2- = 1,4-benzenedicarboxylate). can be rotated an external magnet. Their shape causes...

The maximum magnetisation (saturation magnetisation) obtainable for iron oxide nanoparticles can be increased by doping the nanocrystals with non-magnetic elements such as zinc. Herein, we closely study how only slightly different synthesis approaches towards doped strongly influence resulting sub-nano/atomic structure. We compare two co-precipitation approaches, where vary base (NaOH versus NH3), and a thermal decomposition route. These methods are most commonly applied ones synthesising...

Abstract Although citrates are commonly used to modify nanoparticles, attention is rarely paid how the modification parameters affect type of adsorption and, thus, possibly, properties modified particles. The relevance this and significant impact it can have demonstrated in study by examining effect pH upon superparamagnetic iron oxide nanoparticles (SPIONs) with citrate, using a citrate concentration that yields high molecular surface density but induces almost no coordination pressure....

Magnetic particle spectroscopy (MPS) is used in this work to obtain a magnetic fingerprint signal from anisotropic supraparticles, i.e., microrods assembled superparamagnetic iron oxide nanoparticles. Exceeding its intended purpose of nanoparticle characterization for biomedical imaging, it shown that MPS capable resolving structural differences between the alignment individual nanoparticles and isotropic counterpart. Additionally, orientation-dependent variations supraparticles are...

Abstract Oxidative precipitation is a facile synthesis method to obtain ferromagnetic iron oxide nanoparticles from ferrous salts—with unexplored potential. The concentration of base and oxidant alone strongly affects the particle's structure thus their magnetic properties despite same material, magnetite (Fe 3 O 4 ), obtained when precipitated with potassium hydroxide (KOH) sulfate (FeSO ) treated nitrate (KNO at appropriate temperature. Depending on concentrations, it possible series...

Slight mechanical damage on surfaces or coatings caused, for example, by shear stress, is hardly detectable simple means. Therefore, stress indicator particles the creation of “interactive and communicating” are presented. These core‐shell supraparticles obtained a two‐step spray‐drying assembly process from nanoparticle dispersions. Three different types nanoparticles used to create supraparticles: dye‐doped silica responsible fluorescence signal, iron oxide acting as absorber, pure...

Herein, we report on the successful creation of a luminescent micron-sized magnet.

The determination of induced mechanical forces in ball mills is an ongoing problem, which so far mainly addressed by simulations. Herein, we suggest utilizing superparamagnetic microballoons as sensor particles for stress. defined assembly nanoparticles yields with hollow cores, makes them susceptible to forces. It shown that the structure continuously fragmented under static or dynamic force application. By use magnetic particle spectroscopy, these structural changes are readily detected...

Herein, we demonstrate the preparation of magnetic polyamide 11 feedstock powders for powder bed fusion (PBF) using liquid-liquid phase separation and crystallization. By adding nanomaterials during precipitation process, particulate additive is incorporated into polymer matrix. This enables production filled systems at single particle level, which advantageous in terms adjustable strength homogeneity powder. Thermogravimetric analysis used to determine content onset temperature...

Abstract This work reports on a remotely controllable, all‐magnetic reflective diffraction grating‐like optical element for electromagnetic waves in the visible spectrum. The switchable grating is realized by unique interplay between nanostructured superparamagnetic plate‐like microrods and magnetic stray field landscape generated an engineered stripe domain pattern superimposed small external field. It shown that purposeful design of local sources such continuous thin‐film system enables...

A multi-component particle system was developed that combines the properties of white color, light emission and strong magnetism on macroscopic microscopic scale.

Abstract This study demonstrates how the method of thermally assisted oxidative precipitation in water can be opened for—the so far neglected—metal organic iron(II) complexes (herein: citrate) order to obtain, one step, ferromagnetic magnetite nanoparticles, possessing essential ligand properties. Based on a dedicated analysis specific precursor combination with consideration known properties ligand, it is possible identify existing inhibition‐attributes iron organyl such that these...

Herein, the formation of hollow microballoons derived from superparamagnetic iron oxide nanoparticles with silica patches is reported. Depending on experimental conditions, single- or multishelled as well multivesicular structures were obtained. We show how such structural changes follow a lifelike process that based self-directing Pickering emulsions. further demonstrate key toward complex architectures patchy nature nanoparticles. Interestingly, no well-defined ordering particles surface...

Superparamagnetic iron oxide nanoparticles can be assembled to form anisotropic microrod supraparticles with the assistance of a magnetic field during synthesis. Optionally, these microrods furthermore coated thin silica shell. Due their structure, both types aligned in while being dispersed matrix material which cured alignment microrods. In this way, an composite is obtained. Interestingly, it was observed that optical extinction properties for visible light such are direction dependent,...

Herein, we demonstrate the preparation of magnetic polyamide 11 feedstock powders for powder bed fusion (PBF) using liquid-liquid phase separation and crystallization. By adding nanomaterials during precipitation process, particulate additive is incorporated into polymer matrix. This enables production filled systems at single particle level, which advantageous in terms adjustable strength homogeneity powder. Thermogravimetric analysis used to determine content onset temperature...

Smart Surfaces In article number 2000023, Karl Mandel and co-workers present a new type of abrasion indicators based on supraparticles to determine shear stress surface. With these supraparticles, nanoparticular building blocks, smart communicating surface is developed which indicates by luminescent turn-on effect.

Luminomagnetic composites have been synthesized that allow for an individual tuning of luminescence intensity, chromaticity and magnetization by combination superparamagnetic, citrate-stabilized iron oxide nanoparticles with the luminescent MOFs 3∞ [Ln2 (BDC)3 (H2 O)4 ] (Ln=Eu, Tb; BDC2- =terephthalate). The components are arranged to a concept inverse structuring compared previous luminomagnetic MOF@magnetic particle (shell@core) composition so MOF now acts as core is covered magnetic...

In article 2100098, Mandel and co-workers demonstrate how to solve the long known challenge overcome inhibition effects of citrate that are believed hinder iron oxide nanoparticle formation from salt precursors when being present during synthesis. This opens up routes in-situ modification nano oxides, thus making post-synthesis obsolete.