Research on ionic liquids (ILs) has focused on the synthesis of and organic chemistry in ILs. Recently, however, ILs have also received attention from the inorganic materials community. Ionic liquids can act as solvents for reactants and morphology templates for the products at the same time, which enables the synthesis of inorganic materials with novel or improved properties. In principle, the IL can be retrieved after synthesis and thus provides an ecologically friendly and economical approach to inorganic materials. While ILs are promising "all-in-one" solvent/templates for the synthesis of inorganic materials, only a few reports on this topic have appeared; they have mainly focused on ordered metal oxides [1][2][3][4][5] and metal nanoparticles. [6][7][8] For a recent review on the structural organization in ionic liquids, see also ref. [9] Copper(i) chloride is extensively used as a desulfurizing agent in the petrochemical industry and as a catalyst for the denitration of cellulose; [10] there is thus considerable interest in improved CuCl systems. This paper introduces a novel

Ionic liquids (ILs) can add value to many chemical processes. The electrochemistry and the (physical) organic chemistry communities in particular have extensively studied the structure, properties, and reactivities of various ILs and reactions therein. Inorganic and materials chemists are the newest addition to the IL community: over a number of years, various approaches to the fabrication of inorganic solids with unprecedented and sometimes unique structures and properties have been reported. This article summarizes the state of this particular sub-field of IL research and highlights a few promising approaches that not only reproduce conventional synthesis in ILs, but that provide pathways towards new, possibly unknown, inorganics with advantageous properties that cannot (or only with great difficulty) be made via conventional processes.

In the body, nanoparticles can be systemically distributed and then may affect secondary target organs, such as the central nervous system (CNS). Putative adverse effects on the CNS are rarely investigated to date. Here, we used a mixed primary cell model consisting mainly of neurons and astrocytes and a minor proportion of oligodendrocytes to analyze the effects of well-characterized 20 and 40 nm silver nanoparticles (SNP). Similar gold nanoparticles served as control and proved inert for all endpoints tested. SNP induced a strong size-dependent cytotoxicity. Additionally, in the low concentration range (up to 10 μg/ml of SNP), the further differentiated cultures were more sensitive to SNP treatment. For detailed studies, we used low/medium dose concentrations (up to 20 μg/ml) and found strong oxidative stress responses. Reactive oxygen species (ROS) were detected along with the formation of protein carbonyls and the induction of heme oxygenase-1. We observed an acute calcium response, which clearly preceded oxidative stress responses. ROS formation was reduced by antioxidants, whereas the calcium response could not be alleviated by antioxidants. Finally, we looked into the responses of neurons and astrocytes separately. Astrocytes were much more vulnerable to SNP treatment compared with neurons. Consistently, SNP were mainly taken up by astrocytes and not by neurons. Immunofluorescence studies of mixed cell cultures indicated stronger effects on astrocyte morphology. Altogether, we can demonstrate strong effects of SNP associated with calcium dysregulation and ROS formation in primary neural cells, which were detectable already at moderate dosages.

Water-soluble poly(ethylene oxide-block-methacrylic acid) (P(EO-b-MAA)) and poly(ethylene oxide-block-styrene sulfonic acid) (P(EO-b-SSH)) diblock copolymers were used to control the particle morphologies, sizes and size distributions of zinc oxide precipitated from aqueous solution. With P(EO-b-MAA) copolymers, hexagonal prismatic particles form. Their sizes and size distributions depend on the degrees of polymerization of the blocks. With P(EOb-SSH) copolymers, the particle shape reminds one of a "stack of pancakes". These samples have narrow size distributions, regardless of the degrees of polymerization of the P(EO-b-SSH) copolymers. All crystals have a central grain boundary assigned to twinning. There is evidence for P(EO-b-MAA) copolymer adsorption onto the basal planes of the zinc oxide particles, whereas with P(EO-b-SSH) also an adsorption onto the side faces seems possible. The polymers are incorporated to some extent in the crystals and the amount of the polymer incorporated depends on the initial polymer concentration of the reaction solution.

The highly hydrated ionic liquid tetrabutylammonium hydroxide (TBAH) is an efficient ionic liquid precursor (ILP) for the fabrication of zinc oxide mesocrystals. Upon reaction of TBAH with zinc acetate, individual nanometer‐sized ZnO building blocks assemble into highly correlated ZnO mesocrystals. The mesocrystals are up to ca. 10 µm in length and the larger crystals have a channel running along the long crystal axis.

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The morphogenesis, particle size, size distribution, and phase evolution of zinc oxide precipitated in the presence of water-soluble poly(ethylene oxide-block-methacrylic acid) (P(EO-b-MAA)) and poly(ethylene oxide-block-styrene sulfonic acid) (P(EO-b-SSH)) diblock copolymers is reported. Without a polymeric additive, spindlelike particles with a central grain boundary form along with multiply twinned particles. After ∼30 min, the multiple twins are gone, small, needlelike crystals appear, and the sample becomes more polydisperse. With P(EO-b-MAA) copolymers, initially more rounded particles with the same central grain boundary and a narrow size distribution form. They preferentially grow along the crystallographic c-axis and eventually adopt a hexagonal prismatic shape. With P(EO-b-SSH) copolymers, a lamellar intermediate precipitates first. It eventually dissolves and hexagonal prismatic crystals form; in a subsequent growth process unique to these polymeric additives, the crystals grow along the crystallographic a-axis and transform to another morphology termed the "stack of pancakes" shape. Both in the absence of polymer and with P(EO-b-MAA) copolymers, multiple particle generations precipitate. With P(EO-b-SSH) copolymers, no second generation is observed. Nucleation is delayed by the P(EO-b-MAA) copolymers, while P(EOb-SSH) copolymers favor the rapid nucleation of the highly ordered lamellar intermediate.

The microstructure of zinc oxide particles precipitated in the presence of a poly(ethylene oxide-blockmethacrylic acid) (P(EO-b-MAA)) and a poly(ethylene oxide-block-styrene sulfonic acid) (P(EO-b-SSH)) diblock copolymer was investigated. The crystals precipitated with the P(EO-b-MAA) copolymer consist of a region with a lower but still relatively high order close to a central grain boundary and regions of very high order further away from the central grain boundary. Selected area diffraction (SAD) found single crystalline particles in the control sample, confirmed the formation of single crystalline domains with slightly different orientations with the P(EO-b-MAA) copolymer, and confirmed the formation of a mosaic texture with the P(EO-b-SSH) copolymer. High-resolution transmission electron microscopy images exhibit little defects in the control sample. More defects are found close to the central grain boundary in the sample precipitated with P(EO-b-MAA). With the P(EO-b-SSH) copolymer, a single crystal core carries a number of lamellae, which are bent with respect to each other. Powder X-ray diffraction confirms the formation of zincite and shows a reduction of the coherence length when the crystals are precipitated in the presence of the polymers.