Zinc phosphate nanoparticles are prepared via a polyol-mediated synthesis. The nanomaterial turns out to be nonagglomerated and very uniform in size and shape, in particular 20 nm in diameter. X-ray powder diffraction analysis and high-resolution transmission electron microscopy indicate as-prepared nanoparticles to be noncrystalline. To investigate the chemical composition (stoichiometry, material homogeneity, amount of ortho-/metaphosphate, water content, type of surface-allocated adsorbents, differentiation of surface/inner core), X-ray diffraction, NMR-spectroscopy, energy-dispersive X-ray analysis, infrared spectroscopy, and thermal analysis are performed. To validate the local structure and composition, we performed 1 H, 13 C, and 31 P magic angle spinning nuclear magnetic resonance spectroscopy and multidimensional homo-and heteronuclear multiple-pulse solid-state NMR experiments. Moreover, 31 P{ 1 H} rotational echo double-resonance experiments for various spin topologies are analyzed analytically and numerically, in order to differentiate between homogeneous nanoparticles and core-shell nanoparticles. The analysis gives a length scale to homogeneity and for bulk materials allows us to differentiate between mono-and dihydrogen phosphates, and phosphate hydrates.

Glow in the dark: Nanocrystalline CaF2 and CaF2:Ce,Tb particles are produced via a polyol‐mediated synthesis. The nanomaterials are 20 nm in size, monodispersed, nonagglomerated, and redispersible. Excitation and emission spectra of CaF2:Ce,Tb illustrate the luminescence of powder samples, and a suspension in diethylene glycol also shows intense green‐light emission under UV excitation (see image).

Nanopartikel mit lumineszierenden Vitaminen: ZrO(FMN)‐Nanopartikel, die Flavinmononucleotid als Lumineszenzfarbstoff enthalten, bilden einen neuen Typ von leicht herstellbaren und biokompatiblen Lumineszenzmarkern. Basierend auf fluoreszenzfarbstoffmodifiziertem Zirconiumphosphat können unterschiedliche Emissionsfarben ebenso wie eine schaltbare Fluoreszenz realisiert werden.

A wide variety of nanoscale hollow spheres can be obtained via a microemulsion approach. This includes oxides (e.g., ZnO, TiO2, SnO2, AlO(OH), La(OH)3), sulfides (e.g., Cu2S, CuS) as well as elemental metals (e.g., Ag, Au). All hollow spheres are realized with outer diameters of 10−60 nm, an inner cavity size of 2−30 nm and a wall thickness of 2−15 nm. The microemulsion approach allows modification of the composition of the hollow spheres, fine-tuning their diameter and encapsulation of various ingredients inside the resulting “nanocontainers”. This review summarizes the experimental conditions of synthesis and compares them to other methods of preparing hollow spheres. Moreover, the structural characterization and selected properties of the as-prepared hollow spheres are discussed. The latter is especially focused on container-functionalities with the encapsulation of inorganic salts (e.g., KSCN, K2S2O8, KF), biomolecules/bioactive molecules (e.g., phenylalanine, quercetin, nicotinic acid) and fluorescent dyes (e.g., rhodamine, riboflavin) as representative examples.

Synthesis of nanoparticles in high‐boiling alcohols (so‐called polyol synthesis) and surface functionalization of nanoparticles with polyethylene glycol (so‐called PEGylation) in combination with certain heating are often accompanied with an intense fluorescence in the blue to green spectral range. Based on the polyol synthesis of Zn3(PO4)2 nanoparticles and a critical consideration of the relevant experimental conditions—including the presence of nanoparticles, the role of dissolved metal salts (ZnCl2, MgCl2, KCl), the type of the polyol (DEG, GLY, PEG400), the temperature and time of heating (150–230 °C, 1–6 h)—we can correlate the observed fluorescence to the formation of carbon dots (C‐dots) stemming from thermal decomposition (i.e., dehydration and carbonization) of the polyol. Thus, the thermal decomposition of polyols results in C‐dots with a diameter of 3–5 nm at narrow size distribution. The formation of C‐dots is confirmed by transmission electron microscopy (TEM), high‐resolution TEM (HRTEM), X‐ray powder diffraction (XRD), Fourier‐transform infrared spectroscopy (FT‐IR), and fluorescence spectra.