Because the Roman god Janus was usually represented with two heads placed back to back, term is used for description of particles whose surfaces both hemispheres are different from a chemical point view. So, they could be as building blocks supraparticular assemblies, dual-functionalized devices, particular surfactants if one hemisphere hydrophilic and other hydrophobic, etc. If allow segregation negative charges on positive one, would display giant dipole moment allowing their remote...

Colloidal crystals of various thicknesses were obtained using silica particles as basic units and the Langmuir−Blodgett technique a tool for controlling thickness. Submicronic are first synthesized via sol−gel process then functionalized with an appropriate coupling agent. After compression at surface Langmuir trough to form well-organized two-dimensional array, transferred onto solid substrates. While repeating transfer several times, we formed colloidal that characterized by scanning...

Raspberrylike hybrid organic−inorganic materials consisting of spherical silica beads supporting smaller polystyrene particles were prepared through a heterophase polymerization process. In first step, micrometer-sized synthesized according to procedures inspired from the literature. second poly(ethylene glycol) macromonomer was adsorbed on surface beads. Finally, styrene achieved in water with nonionic surfactant as an emulsifying agent and sodium persulfate initiator. Scanning transmission...

The synthesis of composite particles with original morphologies resulting from the combination an inorganic silica seed and polymer nodules is reported. To promote association between both components, seeds are previously functionalized appropriate coupling agent carrying polymerizable groups. Following classical recipes, emulsion polymerization styrene achieved in presence these surface-modified polystyrene formed exclusively at surface precursors. density agent, however, as well diameter...

Porous golden interiors: Highly organized macroporous metal structures can be synthesized by the preparation of ordered colloidal crystals Langmuir–Blodgett technique and subsequent precision electrodeposition controlled current oscillations. After assembly a bioelectrocatalytic chain in pores, these tailored surfaces used as transducers with currents increased more than one order magnitude (see diagram).

Colloidal particles with a controlled morphology combining both organic and inorganic parts were synthesized through seeded emulsion polymerization process. Silica seed from 50 to 150 nm first surface-modified by adsorption of an oxyethylene-based macromonomer or covalent grafting trialkoxysilane derivative. Then, styrene was carried out in the presence these particles, formation polystyrene nodules being highly favored at silica surface such conditions. While varying different experimental...

Janus silica nanoparticles, regioselectively functionalized by two different chemical groups, were synthesized through a multistep procedure based on the use of polystyrene nodule as protecting mask.

Nanostructured metallic platforms for Raman enhancement were fabricated using Langmuir−Blodgett and electron beam (e-beam) lithography techniques. The gold inscribed on thin glass slides with the purpose of them in a transmission geometry experimental setup under confocal microscope. plasmon frequency nanostructures was determined visible−near-infrared range various pattern sizes prepared by transfer e-beam lithography. surface factors monolayer azobenzene molecules adsorbed through thiol...

Microelectrode arrays (MEAs) are appealing tools to probe large neural ensembles and build prostheses. Microelectronics microfabrication technologies now allow building high-density MEAs containing several hundreds of microelectrodes. However, major problems become limiting factors when the size microelectrodes decreases. In particular, regarding recording activity, intrinsic noise level a microelectrode dramatically increases becomes small (typically below 20-μm diameter). Here, we propose...

Abstract Macroporous materials with a sophisticated architecture are obtained by electrochemical deposition of gold or polypyrrole in colloidal‐crystal templates. The Langmuir–Blodgett technique enables assembly sub‐micrometric silica‐particle monolayers on conductive substrates, thus leading to colloidal superstructures an unprecedented control their features at the single‐bead‐layer level. This allows integration deliberate planar defects elaboration well‐defined gradients terms sphere...

Abstract Porous gold structures with a well‐defined pore size and thickness are obtained through electrochemical deposition of in colloidal crystal template synthesized by the Langmuir–Blodgett (LB) technique. Cylindrical wires were used as substrates for LB successive monolayers silica particles various sizes, electrodeposition this inorganic led to homogeneous, porous metal structure. These materials characterized typical experiments showed high surface‐to‐volume ratios promising features...

Abstract Water splitting has become a sustainable and clean alternative for hydrogen production. Commonly, the efficiency of such reactions is intimately related to physico‐chemical properties catalysts that constitute electrolyzer. Thus, development simple fast methods evaluate electrocatalytic an electrolyzer highly required. In this work, we present unconventional method based on combination bipolar electrochemistry light‐emitting diodes, which allows evaluation performance two types...

Silica/polystyrene nanocomposite particles with different morphologies were synthesized through emulsion polymerization of styrene in the presence silica previously modified by gamma-methacryloxypropyltrimethoxysilane (MPS). Grafting silane molecule was performed direct addition MPS to aqueous suspension an anionic surfactant under basic conditions. The grafting density on surface determined using depletion method and plotted against initial concentration. influence density, size...

Titanium dioxide open-cell macro-cellular foams have been generated with emphasis toward controlling macro-, meso- and microstructures thus reaching hierarchically organized inorganic architectures. At the macroscopic length scale a non-static air–liquid foam strategy allows strong control over morphologies. and/or nanoscopic scales various mesogenic templates or latex colloids used to promote mesoporosity. Among strategies in use, Pluronic copolymer P-123 combined...

Abstract The immobilization of bilirubin oxidase (BOD) on macroporous gold electrodes for the optimization bioelectrocatalytic activity is described. A mutant S362C (cys‐BOD) engineered with a cysteine residue located purpose at enzyme surface close to T1 active center was used. It allows attachment in one‐step self‐assembled monolayer through reaction between thiol group and metal surface. BOD wild type allowed high retention perfect control overall loading due fine‐tuning structure....

Abstract Summary: Polymer latex particles were synthesized in the presence of inorganic particles, which had been organically‐modified to promote favorable interactions with growing macromolecules. The organic modification was performed using three different routes: (1) surface covalent grafting vinyl trialkoxysilanes, (2) adsorption polyethylene glycol‐based macromonomers, and (3) bulk through ion exchange cationic monomers or initiators. Two types mineral studied: commercial self‐prepared...

Abstract Polymer/silica and polymer/Laponite nanocomposite colloids with various morphologies have been elaborated through emulsion polymerization using a polymerizable organosilane (route I) methyl methacrylate‐terminated macromonomer II) as coupling agents. Depending on the synthetic strategy nature of mineral particles, either core‐shell, raspberry‐like, multipod‐like, currant bun or inverted core‐shell (the forming shell) were achieved. Beyond control particle shape, we demonstrated that...

A bottom-up approach is proposed for the design of a fully integrated miniaturized electrochemical cell with independently addressable cylindrical macroporous electrodes. The presented strategy allows excellent control over pore size, thickness each electrode, as well their separation gap. Such coaxial architectures are potentially suitable elaboration devices such (bio)fuel cells, supercapacitors, or biosensors. As service to our authors and readers, this journal provides supporting...

The grafting and catalytic activity of a metathesis catalyst on well defined silica nanoparticles is described. aim this was to test the catalysis properties ligand-linked in ring-opening polymerization also possibility obtain controlled hybrid materials. This carried out by reaction synthesized hydroxy functionalized phosphine Cy2P(CH2)10OH with Cl2Ru(PPh3)2(CH–Ph), leading bearing group at end ligand. reacted diameter 200 nm, that had acyl chloride functions their surface. density...