A procedure for the fabrication of nano-structured micropatterns by direct UV photo-patterning of a monolayer of a self-assembled block copolymer/transition metal hybrid structure is described. The method exploits the selective photochemical modification of a self-assembled monolayer of hexagonally ordered block copolymer micelles loaded with a metal precursor salt. Solvent development of the monolayer after irradiation results in the desired pattern of micelles on the surface. Subsequent plasma treatment of the pattern leaves ordered metal nanodots. The presented technique is a simple and low-cost combination of ‘top-down’ and ‘bottom-up’ approaches that allows decoration of large areas with periodic and aperiodic patterns of nano-objects, with good control over two different length scales: nano- and micrometres.

The synthesis of 2,3,4-tris(11‘-methacryloylundecyl-1‘-oxy)benzenesulfonic acid and its sodium salt is described. The thermal behavior of the compounds was investigated by a combination of polarizing optical microscopy and differential scanning calorimetry. The sodium salt forms a hexagonal columnar disordered phase (Colhd), whereas the acid is a crystalline compound. X-ray scattering analysis and force-field-based molecular modeling provided insight into the molecular arrangement in the mesophase. The sulfonate groups are confined in the center of the columns, preforming a potential ion-transport channel along the column axis. Thin films of the sodium sulfonate were photopolymerized in the mesomorphous state, yielding free-standing foils with embedded potential ion channels.

A new spectroscopic cell has been designed for studying model catalysts using in situ or operando X-ray absorption spectroscopy. The setup allows gas treatment and can be used between 100 and 870 K. Pressures from 10(-3) Pa up to 300 kPa can be applied. Measurements on model systems in this particular pressure range are a valuable extension of the commonly used UHV characterization techniques. Using this setup, we were able to analyze the Au L3 EXAFS of a silica wafer covered with sub-monolayer concentrations of gold (0.05 ML). By modifying the sample holder, powder catalysts can also be analyzed under plug-flow conditions. As an example, the reduction of a Au/SiO2 powder catalyst prepared from HAuCl4 was followed.

Summary: Novel carboxy (COOH)‐functionalized mesoporous polystyrene membranes were prepared from polystyrene‐block‐poly(D,L‐lactide) (PS‐b‐PLA) diblock copolymers through the selective degradation of the PLA block. The combination of atom transfer radical polymerization (ATRP) and ring‐opening polymerization (ROP) techniques enabled the synthesis of nanostructured diblock copolymers possessing carboxylic acid functionality at the junction between both blocks. Such copolymers were subjected to shear flow through the use of a channel die to align their nanodomains. Under mild alkaline conditions, the quantitative hydrolysis of the polyester nanodomains afforded mesoporous materials with COOH‐coated pore walls. The PS‐b‐PLA precursors as well as the resulting porous systems were carefully analyzed by size exclusion chromatography (SEC), 1H NMR, scanning electron microscopy (SEM), and two‐dimensional small‐angle X‐ray scattering (2‐D SAXS). Moreover, the specific surface area and pore size distribution were determined by nitrogen sorption porosimetry.

There is considerable interest in the fabrication of metal and metal oxide nanostructures for applications in fields of technology such as molecular electronics, biosensors, and materials science. [1][2][3][4][5] Specifically, gold nanodots are of interest for their optical, conductive, and catalytic properties. [6][7][8][9] Different approaches have been followed for the creation of controlled patterns of gold nanoparticles and nanowires on surfaces, either by preparing the particles in solution and then depositing them on a surface, or by generating the structure directly on the surface. In the first case, fabrication of defined aperiodic patterns requires local control of the deposition of the particles, [10,11] typically achieved by photoresist technology. [12] In the second case, particle formation must be effected with local control. Here, particle size, size uniformity, and interparticle distances are critical issues.There are examples of both approaches where an electron beam (e-beam) has been used to define chemical patterns either for the guided adsorption of solution-synthesized particles, [13] or for the direct modification of films of pre-made nanoparticles or of gold solutions. [14,15] We have previously shown that rather regular patterns of metal and metal oxide nanodots on surfaces can be obtained by selfassembly of monofilms from block-copolymer micelles with metal precursor salts sequestered in their cores. [16] Under the right conditions, the micelles spontaneously form a closed monofilm with hexagonal order. Subsequent plasma treatment has been employed to reduce the metal salt and remove the organic polymer completely, to yield a single metal nanoparticle per micelle at the sites of the micelle cores, that is, in the regular pattern of the micelles. To create aperiodic patterns of gold nanodots, we took advantage of the fact that the micellar layer can serve as an ebeam negative resist. [17] As the resist contains nanoscopic deposits of a metal salt, it is possible to create patches of nanodots by plasma treatment of the developed films, that is, the functional identities are generated from the resist with a minimum of process steps.Although the e-beam proved to be a successful choice for direct lithography of the micellar layer, there are limitations because of the very high doses that were needed to pin the irradiated micelles effectively to the substrate. In detail, these are electrostatic charging and the concurrent beam deflection, slow writing rates, and a limitation in the choice of the substrate. Here, a focused ion beam (FIB) system is an interesting and in some cases superior alternative that has proven to be a versatile tool for micro-and nanodevice prototyping. FIB systems can be used for imaging, high-resolution milling, and direct modification of a resist layer and self-assembled monolayers. [18,19] Furthermore, commercially available FIB systems have reached a similar resolution as e-beam systems. As a result of the higher mass of ions with respect to electrons, in FIB lithogra...

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