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Water-in-oil microemulsions, as stable colloidal dispersions from quasi-ternary mixtures, have been used in diverse applications, including nanoreactors for confined chemical processes. Their use as soft templates not only includes nanomaterial synthesis but also the interfacial assembly of nanoparticles in hybrid nanostructures. Especially the hierarchical arrangement of different types of nanoparticles over a surface in filament networks constitutes an interesting bottom-up strategy for facile and tunable film coating. Herein, we demonstrate the versatility of this surface assembly from microemulsion dispersions. Transmission and Scanning Electron Microscopy, in addition to UV–Vis Transmittance Spectroscopy, proved the assembly tunability after solvent evaporation under different conditions: the nanostructured films can be formed over different surfaces, using different compositions of liquid phases, as well as with the incorporation of different nanoparticle materials while keeping equivalent surface functionalization. This offers the possibility of adapting different components and conditions for coating tuning on a larger scale with simple procedures. [ABSTRACT FROM AUTHOR]

Localized surface plasmon resonances on noble metal nanoparticles (NPs) can efficiently drive reactions of adsorbed ligand molecules and provide versatile opportunities in chemical synthesis. The driving forces of these reactions are typically elevated temperatures, hot charge carriers, or enhanced electric fields. In the present work, dehalogenation of halogenated thiophenols on the surface of AuNPs has been studied by surface enhanced Raman scattering (SERS) as a function of the photon energy to track the kinetics and identify reaction products. Reaction rates are found to be surprisingly similar for different halothiophenols studied here, although the bond dissociation energies of the C–X bonds differ significantly. Complementary information about the electronic properties at the AuNP surface, namely, work-function and valence band states, has been determined by x-ray photoelectron spectroscopy of isolated AuNPs in the gas-phase. In this way, it is revealed how the electronic properties are altered by the adsorption of the ligand molecules, and we conclude that the reaction rates are mainly determined by the plasmonic properties of the AuNPs. SERS spectra reveal differences in the reaction product formation for different halogen species, and, on this basis, the possible reaction mechanisms are discussed to approach an understanding of opportunities and limitations in the design of catalytical systems with plasmonic NPs. [ABSTRACT FROM AUTHOR]

In this study, a low‐melting organic‐inorganic crystalline ionic liquid compound, N‐butyl pyridinium tetrachlorido ferrate (III) is described. The material can easily be synthesized using a one‐pot approach in an ionic liquid medium. Single‐crystal X‐ray diffraction confirms that the basic inorganic block is [FeCl4]−, which is counterbalanced by an N‐butyl pyridinium cation. The compound exhibits a melting point of 37.6 °C by differential scanning calorimetry, which is among the lowest values for a pyridinium‐based metal‐containing ionic liquid. The material shows promising electrochemical behavior at room temperature in both aqueous and nonaqueous solvents, and at elevated temperatures in its pure liquid state. Given its appreciable solubility in both water and acetonitrile, the compound can act as a redox‐active species in a supporting electrolyte for redox flow battery applications. These classes of low‐melting ionic solids with long‐range order and interesting electrochemical applications are potential candidates for a range of green energy storage and harvesting systems. [ABSTRACT FROM AUTHOR]

Antimicrobial polymers are a promising alternative to conventional antibiotics in the fight against antimicrobial resistance. Cationic bottle brush copolymers have shown to be superior to linear topologies in previous studies. Herein, the aspect ratio of such polymers is varied creating differently shaped confined unimolecular structures with varying degrees of side chain mobility. Using reversible addition‐fragmentation chain‐transfer (RAFT) polymerization, bottle brushes are produced in a one‐pot procedure. The morphology is confirmed by atomic force microscopy. The hydrophobicity, as determined via high performance‐liquid chromatography (HPLC) analysis, is drastically influenced by the topology. Using Fourier‐transform infrared (FTIR) spectroscopy, it is found that polymers with a high side chain mobility and increased global hydrophilicity, are less hydrated, and have stronger intramolecular hydrogen bonds. A phase segregated morphology leading to unimolecular micellization is assumed. Biological tests reveal increased antimicrobial activity for such segregated polymers. Their excellent hemocompatibility results in highly selective antimicrobial polymers whose adaptability seems to be a key feature in their excellent performance. This study highlights the tremendous importance of structural control in antimicrobial polymers. [ABSTRACT FROM AUTHOR]