The Influence of TiO Nanoparticles Morphologies on the Performance of Lithium-Ion Batteries.

Anode materials based on the TiO nanoparticles of different morphologies were prepared using the hydrothermal method and characterized by various techniques, such as X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), and N absorption. The TiO nanoparticles prepared were used as anode materials for lithium-ion batteries (LIBs), and their electrochemical properties were tested using discharging/charging measurements. The results showed that the initial morphology of the nanoparticles plays a minor role in battery performance after the first few cycles and that better capacity was achieved for TiO nanobelt morphology.

C3-Alkylation of furfural derivatives by continuous flow homogeneous catalysis.

The C3-functionalization of furfural using homogeneous ruthenium catalysts requires the preinstallation of an -directing imine group, as well as high temperatures, which did not allow scaling up, at least under batch conditions. In order to design a safer process, we set out to develop a continuous flow process specifically for the C3-alkylation of furfural (Murai reaction). The transposition of a batch process to a continuous flow process is often costly in terms of time and reagents.

Revisiting Alkoxysilane Assembly on Silica Surfaces: Grafting versus Homo-Condensation in Solution.

Silica surface functionalization is often done through the condensation of functional silanes on silanols, silica surfaces' terminal groups. APTES, aminopropyltriethoxysilane, is widely used due to its assumed high reactivity with silanols, kinetically promoted by the catalytic action of the terminal amine function. Here, we revisit, based on a quantitative analysis by solid-state Si NMR, the assembly of this silane on silica surfaces to investigate whether its presence results from grafting, i.

Synthesis of TiO Nanobelt Bundles Decorated with TiO Nanoparticles and Aggregates and Their Use as Anode Materials for Lithium-Ion Batteries.

TiO nanobelt bundles decorated with TiO aggregates were prepared using an easy and scalable hydrothermal method at various temperatures (170, 190, 210, and 230 °C). It was demonstrated that the synthesis temperature is a key parameter to tune the number of aggregates on the nanobelt surface. Prepared TiO aggregates and nanobelt bundles were used to design anode materials in which the aggregates regulated the pore size and connectivity of the interconnected nanobelt bundle structure.

Silica-coated gold nanorods biofunctionalization for localized surface plasmon resonance (LSPR) biosensing.

We introduce here the engineering of nanobiosensors designed from gold nanorods coated with an ultrathin layer of silica (AuNR@SiO) and biofunctionalized with antibodies for the Localized Surface Plasmon Resonance (LSPR) biosensing of proteins. Despite the outstanding properties of AuNRs, their use for LSPR biosensing is limited due to the presence of the surfactant cetyltrimethylammonium bromide (CTAB) - mandatory for their synthesis - which forms a strongly-bounded and positively-charged bilayer at their surface and significantly complicates their bio-functionalization. When coated with a thin layer of silica, these nanomaterials exhibit an improved sensitivity to refractive index change which augurs for better analytical performances.

Gold Nanorods for LSPR Biosensing: Synthesis, Coating by Silica, and Bioanalytical Applications.

Nanoparticles made of coinage metals are well known to display unique optical properties stemming from the localized surface plasmon resonance (LSPR) phenomenon, allowing their use as transducers in various biosensing configurations. While most of the reports initially dealt with spherical gold nanoparticles owing to their ease of synthesis, the interest in gold nanorods (AuNR) as plasmonic biosensors is rising steadily. These anisotropic nanoparticles exhibit, on top of the LSPR band in the blue range common with spherical nanoparticles, a longitudinal LSPR band, in all respects superior, and in particular in terms of sensitivity to the surrounding media and LSPR-biosensing.

Zn-Cu Alloy Nanofoams as Efficient Catalysts for the Reduction of CO to Syngas Mixtures with a Potential-Independent H /CO Ratio.

Alloying strategies are commonly used to design electrocatalysts that take on properties of their constituent elements. Herein, such a strategy is used to develop Zn-Cu alloyed electrodes with unique hierarchical porosity and tunable selectivity for CO versus H reduction. By varying the Zn/Cu ratio, tailored syngas mixtures are obtained without the production of other gaseous products, which is attributed to preferential CO- and H -forming pathways on the alloys.

Control of calcium accessibility over hydroxyapatite by post-precipitation steps: influence on the catalytic reactivity toward alcohols.

Hydroxyapatites are increasingly used as heterogeneous catalysts since they present atypical behaviours for many acid base reactions. The aim of this study was to discuss the possible involvement of Ca Lewis and/or PO-H Brønsted acid sites belonging to the hydroxyapatite system in the conversion of 2-methylbut-3-yn-1-ol, a model molecule that is known to account for the acid base properties, and of ethanol into n-butanol. A series of hydroxyapatite samples with similar bulk properties was prepared from a lone precipitation batch, but by varying the conditions of the washing and drying steps.

The genesis of a heterogeneous catalyst: in situ observation of a transition metal complex adsorbing onto an oxide surface in solution.

Understanding the interactions between metal complexes and oxide surfaces is crucial to the synthesis of supported metal catalysts. Recently developed in situ techniques have made it possible to closely characterize the solid/liquid interface. For the first time, the adsorption of platinum complexes on alumina and silica has been probed using a quartz crystal microbalance; we were able to observe the adsorption of metal complexes in real time, and to observe the reversibility of this adsorption.

Confinement in nanopores at the oxide/water interface: modification of alumina adsorption properties.

There is limited knowledge on the influence of the pore size on surface phenomena (adsorption, dissolution, precipitation, etc.) at the oxide/water interface and a better understanding of the space confinement in nanoscale pores should have practical implications in different areas, such as transport of contaminants in the environment or heterogeneous catalyst preparation, to name a few. To investigate the modifications of the oxide adsorption properties at the oxide/water interface in a confined environment, the surface acidobasic and ion adsorption properties of six different aluminas (5 porous commercial aluminas with pore diameters ranging from 25 to 200 A and 1 non-porous alumina) were determined by means of acid-base titration and Ni(II) adsorption.

Polyoxomolybdate-stabilized Ru(0) nanoparticles deposited on mesoporous silica as catalysts for aromatic hydrogenation.

We use polyoxometalates as precursors for the preparation of heterogeneous catalysts. In the starting molecular precursor [{Ru(C6Me6)}(2)Mo5O18{Ru(C6Me6)(H2O)}], three ruthenium arene fragments are supported on a formally lacunary Lindqvist-type polyoxomolybdate. This species was introduced by incipient wetness impregnation into the porosity of a SBA-15-type mesoporous silica.