Confinement of a bioinspired nonheme Fe(II) complex in 2D hexagonal mesoporous silica with metal site isolation.

A mixed amine pyridine polydentate Fe(II) complex was covalently tethered in hexagonal mesoporous silica of the MCM-41 type. Metal site isolation was generated using adsorbed tetramethylammonium cations acting as a patterned silanol protecting mask and trimethylsilylazane as a capping agent. Then, the amine/pyridine ligand bearing a tethering triethoxysilane group was either grafted to such a pretreated silica surface prior to or after complexation to Fe(II).

Critical role of surface chemical modifications induced by length shortening on multi-walled carbon nanotubes-induced toxicity.

Given the increasing use of carbon nanotubes (CNT) in composite materials and their possible expansion to new areas such as nanomedicine which will both lead to higher human exposure, a better understanding of their potential to cause adverse effects on human health is needed. Like other nanomaterials, the biological reactivity and toxicity of CNT were shown to depend on various physicochemical characteristics, and length has been suggested to play a critical role. We therefore designed a comprehensive study that aimed at comparing the effects on murine macrophages of two samples of multi-walled CNT (MWCNT) specifically synthesized following a similar production process (aerosol-assisted CVD), and used a soft ultrasonic treatment in water to modify the length of one of them.

Self-assembled monolayer-functionalized half-metallic manganite for molecular spintronics.

(La,Sr)MnO(3) manganite (LSMO) has emerged as the standard ferromagnetic electrode in organic spintronic devices due to its highly spin-polarized character and air stability. Whereas organic semiconductors and polymers have been mainly envisaged to propagate spin information, self-assembled monolayers (SAMs) have been overlooked and should be considered as promising materials for molecular engineering of spintronic devices. Surprisingly, up to now the first key step of SAM grafting protocols over LSMO surface thin films is still missing.

Spontaneous grafting of diazonium salts: chemical mechanism on metallic surfaces.

The spontaneous reaction of diazonium salts on various substrates has been widely employed since it consists of a simple immersion of the substrate in the diazonium salt solution. As electrochemical processes involving the same diazonium salts, the spontaneous grafting is assumed to give covalently poly(phenylene)-like bonded films. Resistance to solvents and to ultrasonication is commonly accepted as indirect proof of the existence of a covalent bond.

Relationship between polypyrrole morphology and electrochemical activity towards oxygen reduction reaction.

The relationship between the morphology of polypyrrole and their electrocatalytic performances towards the oxygen reduction reaction (ORR) in alkaline media is described; annealed polypyrrole with granular- and tubules-like morphology exhibited different catalytic efficiencies.

Metal-free nitrogen-containing carbon nanotubes prepared from triazole and tetrazole derivatives show high electrocatalytic activity towards the oxygen reduction reaction in alkaline media.

High-performance oxygen reduction reaction (ORR) catalysts based on metal-free nitrogen-containing precursors and carbon nanotubes are reported. The investigated systems allow the evaluation of the effect of nitrogen-containing groups towards ORR and the results show that the catalysts are compatible with the conditions encountered in alkaline fuel cells, exhibiting good catalytic activity and stability compared with conventional Pt/C electrocatalyst.

Cyanide-bridged NiCr and alternate NiFe-NiCr magnetic ultrathin films on functionalized Si(100) surface.

Sequential growth in solution (SGS) was performed for the magnetic cyanide-bridged network obtained from the reaction of Ni(H(2)O)(2+) and Cr(CN)(6)(3-) (referred to as NiCr) on a Si(100) wafer already functionalized by a Ni(II) complex. The growth process led to isolated dots and a low coverage of the surface. We used the NiFe network as a template to improve the growth of the magnetic network.

Sequential growth in solution of NiFe Prussian blue coordination network nanolayers on Si(100) surfaces.

Controlling the elaboration of Coordination Networks (CoNet) on surfaces at the nanoscale remains a challenge. One suitable technique is the Sequential Growth in Solution (SGS), which has the advantage to be simple, cheap and fast. We addressed two issues in this article: i) the controlled synthesis of ultra thin films of CoNet (thickness lower than 10 nm), and ii) the investigation of the influence of the precursors' concentration on the growth process.

Electrochemical performance of annealed cobalt-benzotriazole/CNTs catalysts towards the oxygen reduction reaction.

One of the major limitations yet to the global implementation of polymer electrolyte membrane fuel cells (PEMFCs) is the cathode catalyst. The development of efficient platinum-free catalysts is the key issue to solve the problem of slow kinetics of the oxygen reduction reaction (ORR) and high cost. We report a promising catalyst for ORR prepared through the annealing treatment under inert conditions of the cobalt-benzotriazole (Co-BTA) complex supported on carbon nanotubes (CNTs).

3D amino-induced electroless plating: a powerful toolset for localized metallization on polymer substrates.

The "3D amino-induced electroless plating" (3D-AIEP) process is an easy and cost-effective way to produce metallic patterns onto flexible polymer substrates with a micrometric resolution and based on the direct printing of the mask with a commercial printer. Its effectiveness is based on the covalent grafting onto substrates of a 3D polymer layer which presents the ability to entrap Pd species. Therefore, this activated Pd-loaded and 3D polymer layer acts both as a seed layer for electroless metal growth and as an interdigital layer for enhanced mechanical properties of the metallic patterns.

Role of substrate wettability in the "bubble deposition method" applied to the CeVO4 nanowire films.

Homogeneous two-dimensional structures of CeVO(4) nanowires (NWs) deposited on silicon substrates are obtained by means of the bubble deposition method (BDM). Surface wettability (i.e.

Zn-porphyrin/Zn-phthalocyanine dendron for SWNT functionalisation.

SWNT-porphyrin/phthalocyanine conjugates are described and fully characterised; their optical and electrochemical properties are investigated.

Growth and density control of nanometric nickel-iron cyanide-bridged objects on functionalized Si(100) surface.

Isolated nanometric objects of the nickel-iron cyanide-bridged coordination network are obtained by a sequential growth on "molecular seeds" anchored on Si(100) surfaces. Control of the density and the size of the nano-objects is achieved by imposing a growth process without side nucleation.

ABS polymer electroless plating through a one-step poly(acrylic acid) covalent grafting.

A new, efficient, palladium- and chromium-free process for the electroless plating of acrylonitrile-butadiene-styrene (ABS) polymers has been developed. The process is based on the ion-exchange properties of poly(acrylic acid) (PAA) chemically grafted onto ABS via a simple and one-step method that prevents using classical surface conditioning. Hence, ABS electroless plating can be obtained in three steps, namely: (i) the grafting of PAA onto ABS, (ii) the copper Cu(0) seeding of the ABS surface, and (iii) the nickel or copper metallization using commercial-like electroless plating bath.

Efficient functionalization of carbon nanotubes with porphyrin dendrons via click chemistry.

The attempt to decorate carbon nanotubes with organic molecules as a powerful means to form new functional materials has attracted broad attention in the scientific community. Here, we report the functionalization of single-walled carbon nanotubes (SWNTs) with zinc porphyrins (ZnP) using very mild conditions to afford a series of SWNTs-ZnP (1 and 2) electron donor-acceptor conjugates. Owing to the presence of either one or two ZnP, introduced via "click chemistry", different absorption cross sections were realized.

A new approach to grafting a monolayer of oriented Mn12 nanomagnets on silicon.

The functionalisation of a Si(100) silicon wafer allows for the oriented grafting of a monolayer of Mn12 nanomagnets using a two-step procedure.