Meso/Macroporous Inorganic Oxide Monoliths from Polymer Foams

Abstract

PDMS stamps were inked with C 16 SH by rubbing the surfaces of stamps with a cotton swab pre-soaked with a solution of 20 mM [27] C 16 SH in ethanol followed by drying in a stream of nitrogen. The patterned SAMs were formed by pressing the inked stamps in contact with the gold substrates for about 1 min. The substrate was then washed with ethanol and DI water and blown dry in N 2 stream.Underpotential Deposition: The procedure for underpotentially depositing silver and copper has been described previously [8]. For the upd of copper onto gold, the working electrode was cycled at a rate of 10 mV s ±1 from 0 to 450 mV and emersed from the electrochemical cell under a controlled potential on the third anodic scan at 135 mV (vs. Cu wire) for u Cu = 0.6. For the upd of silver, the working electrode was cycled at 10 mV s ±1 from 0 to 650 mV and emersed under a controlled potential on the third cathodic scan at 60 mV (vs. Ag wire) for u Ag = 0.9. After emersion, the substrates were rinsed with absolute ethanol and blown dry in a N 2 stream. The coverages of the upd adlayers were determined by XPS as described previously [24].Desorption of SAMs: The SAM-patterned electrodes were cycled at 50 mV s ±1 from 0.05 V to ±1.4 V (vs. Ag/AgCl) in 0.5 M KOH in ethanol to reductively desorb the SAMs from the substrates [17]. During the final scan, the potential was held at ±1.4 V and the substrate was removed from the electrochemical cell under controlled potential. The sample was rinsed with absolute ethanol and blown dry in a N 2 stream.Formation of PM Patterns: Dilute solutions of diazomethane in ether were carefully prepared according to a literature procedure [28]. Warning: diazomethane is highly explosive and highly toxic and should be handled with extreme care. The concentration of diazomethane in ether was determined by titration with benzoic acid. Substrates were placed in an ethereal solution containing a desired concentration of DM for a predetermined period of time at 0 C. The amount of time the samples were exposed to air after emersion from the electrochemical cell and prior to DM exposure was~1±2 min.Characterization: AFM images of PM films were obtained with a Nanoscope III scanning probe microscope (SPM) equipped with a J piezoelectric scanner (Digital Instruments, Santa Barbara, CA). An area of 120 120 lm 2 was scanned in tapping mode to attain the height images under an ambient laboratory environment. The images were plane fitted and filtered to remove noise using the instrument software.

Role of PPO–PEO–PPO triblock copolymers in phase transitions of a PEO–PPO–PEO triblock copolymer in aqueous solution

“…Variations of PPO/PEO ratio and molecular weight (PEO and PPO block lengths) lead to the production of triblock copolymers with various compositions and properties that meet the specific requirements in numerous applications such as detergents [5], dispersion stabilizers [18], foaming agents [19], emulsifiers [20], drug solubilizers [21], drug carriers for controlled delivery and release [22][23][24], etc.…”

Progress in the studies of low-molecular mass gelators with unusual properties

“…To date, studies on gel emulsions have attracted increasing attention because of their promising applications in cosmetics, foods, fuels, explosives, other materials with unusual properties, and template preparation of low-density materials, etc. [48,[54][55][56][57].…”

Hierarchically structured meso-macroporous aluminosilicates with high tetrahedral aluminium content in acid catalysed esterification of fatty acids

“…Recent studies highlight the promising superiority of hierarchical meso-macrostructured materials in large series of catalytic reactions [1][2][3][4][5][6][7][8][9][10][11], thanks to improved diffusion and mass transfer properties as well as limitation of poisoning and coking, especially when large molecules are used and reactions are performed in viscous liquid phase [12,13]. A large panel of original strategies, often quite tedious to achieve, have been developed to allow the incorporation of desirable porosities at different length scales into one single body.…”