A controlled quenching process allows the nucleation period to be increased sufficiently, such that high‐resolution transmission electron microscopy can be used to reveal the structural and shape transformations during the onset and development of mesophase ordering of the hexagonally ordered silica–surfactant mesophase MCM‐41 (see scheme).

Reverse micelles of calcium bis(2-ethylhexyl)phosphate (Ca(DEHP) 2 ) were used to synthesize calcium phosphate nanostructures from a reaction mixture initially containing a water-in-cyclohexane emulsion of Ca(DEHP) 2 , ammonium hydrogen phosphate, and triblock copolymer, P123. Bundles of DEHP-coated amorphous calcium phosphate nanofilaments, 2 nm in width and >300 µm in length were formed in the oil layer of a phase-separated reaction mixture prepared at a [Ca]: [PO 4 ] molar ratio of 1:1 and pH of 8.2. The nanofilament bundles were stable in the reverse micelle phase up to around 5 days, after which they transformed into 5-nm-wide surfactant-coated hydroxyapatite nanorods. In contrast, similar experiments at a higher supersaturation level (pH ) 9, [Ca]:[PO 4 ] ) 1.66) produced discrete nanofilaments (100-500 × 10-15 nm in size) that consisted of a linear superstructure based on the side-on stacking of surfactant-coated amorphous calcium phosphate nanorods. Possible factors giving rise to these ordered nanostructures are discussed.

The electrocatalytic reduction of CO2 at carbon-supported Au-Pd core-shell nanoparticles is systematically investigated as a function of Pd shell thickness. Liquid and gas phase products were determined by off-line 1 H NMR and on-line electrochemical mass spectrometry (OLEMS). Our results uncover the relationship between the nature of products generated and the Pd shell thickness. CO and H2 are the only products generated at 1 nm thick shells, while shells of 5 and 10 nm produced HCOO -, CH4 and C2H6. The concentration of HCOO -detected in the electrolyte was dependent on the applied potential, reaching a maximum Faradaic efficiency of 27% at -0.5 V vs. RHE for 10 nm thick shells. We conclude that collisions between absorbed hydrogen at relaxed Pd lattices and strongly bound "COlike" intermediates promote the complete hydrogenation to C1 and C2 alkanes, without the generation of other products such as alcohols and aldehydes.

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