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Behind the scenes: NMR spectroscopy was used to distinguish hydrogen bonding and ion pairing in the activation of imines by a phosphate catalyst (see structures). Hydrogen‐bond strength and the amount of the hydrogen‐bonded species present are decisive for the catalytic reaction and can be manipulated by introducing substituents with different electronic properties. This insight should guide the development of more efficient catalytic systems.

The formation of reversible switchable nanostructures monitored by solution and solid-state methods is still a challenge in supramolecular chemistry. By a comprehensive solid state and solution study we demonstrate the potential of the fivefold symmetrical building block of pentaphosphaferrocene in combination with CuI halides to switch between spheres of different porosity and shape. With increasing amount of CuX, the structures of the formed supramolecules change from incomplete to complete spherically shaped fullerene-like assemblies possessing an Ih-C80 topology at one side and to a tetrahedral-structured aggregate at the other. In the solid state, the formed nano-sized aggregates reach an outer diameter of 3.14 and 3.56 nm, respectively. This feature is used to reversibly encapsulate and release guest molecules in solution.

At platinum electrodes kinetics of the I − /I 3 − electrode reaction were studied at two potential electrolyte systems for dye-sensitized solar cells ͑DSSCs͒ based on binary ionic liquid ͑IL͒ blends, i.e., 1-ethyl-3-methylimidazolium dicyanamide ͓͑EMIM͔ ͓N͑CN͒ 2 ͔͒/1-methyl-3-propylimidazolium iodide ͓͑PMIM͔I͒ and 1-ethyl-3-methylimidazolium tetrafluoroborate ͓͑EMIM͔ ͓BF 4 ͔͒/͓PMIM͔I, respectively. The charge transfer resistances of the electrode reaction were determined via impedance spectroscopy for electrolyte blends at a mixing ratio of ILs of 9 mol % ͓PMIM͔I ͑for ͓EMIM͔͓N͑CN͒ 2 ͔/͓PMIM͔I͒ and 10 mol % ͓PMIM͔I ͑for ͓EMIM͔͓BF 4 ͔/͓PMIM͔I͒ up to 100 mol % ͓PMIM͔I. In addition, the influence of iodine concentration on the electrode reaction was investigated for both electrolyte systems. The measurements were taken in a temperature range of 25 to 60°C to analyze the electrolyte properties in view of thermal stress of the DSSC for later practical application. Furthermore, exchange current densities were determined: the expected Arrhenius behavior was observed. Activation energies were obtained by fitting linearized Arrhenius plots.

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