Materials synthesis in the liquid phase, or wet-chemical synthesis, utilizes a solution medium in which the target materials are generated from a series of chemical and physical transformations. Although this route is central in organic chemistry, for materials synthesis the low operational temperature range of the solvent (usually below 200 °C, in extreme 350 °C) is a serious restriction. Here, salt melt synthesis (SMS) which employs a molten inorganic salt as the medium emerges as an important complementary route to conventional liquid phase synthesis. Depending on the nature of the salt, the operational temperature ranges from near 100 °C to over 1000 °C, thus allowing the access to a broad range of inorganic crystalline materials and carbons. The recent progress in SMS of inorganic materials, including oxide ceramic powders, semiconductors and carbon nanostructures, is reviewed here. We will introduce in general the range of accessible materials by SMS from oxides to non-oxides, and discuss in detail based on selected examples the mechanisms of structural evolution and the influence of synthetic conditions for certain materials. In the later sections we also present the recent developments in SMS for the synthesis of organic solids: covalent frameworks and polymeric semiconductors. Throughout this review, special emphasis is placed on materials with nanostructures generated by SMS, and the possible modulation of materials structures at the nanoscale in the salt melt. The review is finalized with the summary of the current achievements and problems, and suggestions for potential future directions in SMS.

A facile method to fabricate high-surface area functional carbons via convenient "salt templating" is presented. Exemplarily, nitrogen- as well as nitrogen-/boron-co-doped carbons were synthesized using ionic liquids as precursors and eutectics as porogen. The porogen is easily removable with water and the porosities can be adjusted from micro- to mesoporous depending on the salt nature and amount.

Covalent bridges play a crucial role in the folding process of sequence-defined biopolymers. This feature, however, has not been recreated in synthetic polymers because, apart from some simple regular arrangements (such as block co-polymers), these macromolecules generally do not exhibit a controlled primary structure--that is, it is difficult to predetermine precisely the sequence of their monomers. Herein, we introduce a versatile strategy for preparing foldable linear polymer chains. Well-defined polymers were synthesized by the atom transfer radical polymerization of styrene. The controlled addition of discrete amounts of protected maleimide at precise times during the synthesis enabled the formation of polystyrene chains that contained positionable reactive alkyne functions. Intramolecular reactions between these functions subsequently led to the formation of different types of covalently folded polymer chains. For example, tadpole (P-shaped), pseudocyclic (Q-shaped), bicyclic (8-shaped) and knotted (α-shaped) macromolecular origamis were prepared in a relatively straightforward manner.

The synthesis of carbon aerogels by sol–gel like processes, i.e., hard templating, phase demixing, hydrothermal carbonization techniques, as well as by ionothermal syntheses are reviewed. In all these techniques, we start with a liquid reaction solution, wherecontrolled by experimental parameters and structure-directing additivesa porous carbon material with high conductivity, high pore volume, and high specific surface area is obtained. Many of these synthesis approaches give the resulting material in simple, rather sustainable processes, and the structures can be employed directly after isolation without further activation processes. The article will discuss also some applications, such as battery and electrode materials as well as catalyst supports.

Hydrothermal carbonization of carbohydrates, here glucose as a model, in saltwater mixtures results in high surface area carbonaceous materials with surface areas up to 650 m 2 g À1 where porosity is created by aggregation of very small primary nanoparticles, similar to aerogels or high surface area soot. These materials can be obtained by simple washing with water and are useful without further activation processes. Furthermore, no special technical equipment for isolation is needed since the materials are exceptionally stable throughout vacuum drying, thus keeping the overall approach sustainable and very simple. Synthesis and methods Materials and methods D-(+)-Glucose was purchased from Roth Chemicals. Lithium chloride, sodium chloride, potassium chloride and zinc