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A new materials composed of TiFe particles stabilized onto a carbon support is described. The carbon support is derived from a waste from the paper industry called Kraft Black liquor. The particles are generated through an impregnation/reduction process of a mixture of titanium ethoxide and iron nitrate followed by a thermal treatment. The generated particles have been investigated through XPS, XRD and SEM analysis as well as tested for hydrogen storage. The hydrogen storage at 25 °C leads to a capacity of up to 0.5 wt% while at 150 °C, free of the carbon absorption, leads to a capacity of 0.2 wt% without any prior activation process. Novel TiF@carbo(HIPE) materials have been synthesized while employing Kraft black liquor as carbonaceous source. A specific carbo-reduction thermal treatment allows a synergetic TiFe particles external shell reduction concomitant with the surrounding carbonaceous backbone oxidation enhancing thereby the materials specific surface area and associated microporosity. Pre-activation free, TiFe@Carbo(HIPE) can achieve a capacity up to 0.5 wt% at 25 °C where TiFe particles and the carbonaceous host support are acting cooperatively. [Display omitted] • Generation and characterization of carbon from a waste from the paper industry. • Generation of TiFe nanoparticles on the carbon. • Characterization of the TiFe nanoparticles. • Use of the hybrid composite TiFe@Carbon for hydrogen storage. [ABSTRACT FROM AUTHOR]

Dedicated coating materials for anechoism and furtivity in underwater acoustics must exhibit a strong reliability regarding their mechanical resistance to hydrostatic pressure. Soft porous materials, especially, a distribution of soft porous beads within a polyurethane matrix, have been previously proposed as an acoustic insulator device. The purpose of the present letter is to investigate the attenuation efficiency of soft porous silicone beads-based materials while being exposed to uniaxial loads mimicking hydrostatic pressures encountered in underwater acoustics. The acoustic performance of this locally resonant material is then compared to the classical coating technology using micro-balloons. The use of an adapted surfactant (a silicone alkyl polyether compound) in the fabrication process of the soft porous silicone-based beads, obtained through an emulsion templating process, leads to particles exhibiting an open porosity. The (resonant) attenuation of the soft porous beads-based material remains greater than the micro-balloons-based material until several bars. Above this critical resilience value, the mechanical stress irreversibly damages the soft porous beads. [ABSTRACT FROM AUTHOR]

A biopolymer derived from Kraft Black Liquor (KBL), a byproduct of the paper industry composed mainly of lignin and hemicellulose, has been successfully filled with three different types of carbon black (CB) that differ in their specific surface areas, sizes, shapes and surface heteroatoms. These composite CB–KBL dispersions have been subsequently employed to generate porous monoliths through an emulsion-polymerization templating process. After carbonization, the fillers' influence over the resulting carbon monolith structures and textures is investigated. In particular, beyond XRD, Raman spectroscopy demonstrates improved sample structuration through CB filler addition while nitrogen sorption measurements reveal the influence of the fillers over the final composite's porosities. Considering their properties and effectiveness, hydrogen storage at 77 K reveals that some materials offer up to 1.4 wt% of H2 storage capacity, being higher than that of some commercial carbon materials (with the same specific surface) offering 1.2 wt% hydrogen retention. When addressing their electrochemical energy storage properties, some of these electrode materials deliver extremely promising specific capacities and rate capabilities, with values up to 47 mA h g−1 at 1 A g−1 in alkaline electrolyte, higher than those of the well-known "YP-80F" commercial material tested under the same conditions. These enhanced energy storage properties, while employing a high tonnage paper industry by-product as a carbonaceous source and carbon blacks as structural and textural modifiers, render these materials realistic candidates favoring a sustainable energy transition. [ABSTRACT FROM AUTHOR]

Hybrid materials consisting of metallic nanoparticles (NPs) adsorbed on porous polymeric supports have been the subject of intense research for many years. Such materials indeed gain from intrinsic properties, e.g., high specific surface area, catalytic properties, porous features, etc., of both components. Rational design of such materials is fundamental regarding the functionalization of the support surface and thus the interactions required for the metallic NPs to be strongly immobilized at the pore surface. Herein are presented some significant scientific contributions to this rapidly expanding research field. This contribution will notably focus on various examples of such hybrid systems prepared from porous polymers, whatever the morphology and size of the pores. Such porous polymeric supports can display pores with sizes ranging from a few nanometers to hundreds of microns while pore morphologies, such as spherical, tubular, etc., and/or open or closed, can be obtained. These systems have allowed some catalytic molecular reactions to be successfully undertaken, such as the reduction of nitroaromatic compounds or dyes, e.g., methylene blue and Eosin Y, boronic acid-based C–C homocoupling reactions, but also cascade reactions consisting of two catalytic reactions achieved in a row. [ABSTRACT FROM AUTHOR]

This paper addresses the functionalization of doubly porous poly(2-hydroxyethyl methacrylate) (PHEMA)-based networks obtained from the double porogen approach, and their subsequent utilization as catalytic supports in heterogeneous catalysis. Advantage of the availability of hydroxyl groups within the PHEMA-based frameworks was taken through a chemical modification with carbonyldiimidazole. This key activation led to three main functionatization reactions of the materials via nucleophilic substitution or thiol-yne 'click' addition of amino molecules. Further, in-situ generation of gold nanoparticles (GNPs) allowed for the preparation of innovative functionalized biporous GNP@PHEMA materials. The as-obtained hybrid frameworks could efficiently be used as catalytic supports in the reduction of 4-nitrophenol. [ABSTRACT FROM AUTHOR]

Titanium propoxide, titanium isopropoxide, and titanium (triethanolaminato) isopropoxide are proposed as high-performance additives to overcome the oxygen inhibition effects in the free radical photopolymerization of a low-viscosity monomer thin film, under air and upon a low-intensity UV light activation. Indeed, when added to a Type I photoinitiator such as bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide (BAPO), noticeably higher conversions are achieved under air (48% vs. 30%). The in situ formation of Ti-based nanoparticles is also observed. The photochemical properties of these types of Ti-based compounds as well as their interaction with BAPO are investigated by steady-state photolysis and electron spin resonance. Molecular orbital calculations give an interesting insight into the possible reactions. A chemical mechanism is also proposed. [ABSTRACT FROM AUTHOR]

Original porous catalytic supports can be engineered via an effective and straightforward synthetic route to polystyrene-block-poly(d,l-lactide) diblock copolymer precursors displaying an acid-cleavable acetal junction between both blocks. To this purpose, we synthesized an acetal-containing heterodifunctional initiator, thus enabling to combine two different polymerization methods, i.e., first atom transfer radical polymerization (ATRP) of styrene, and then ring-opening polymerization (ROP) of d,l-lactide. Thanks to the labile nature of the acetal junction, oriented porous frameworks could be obtained upon trifluoroacetic acid-mediated cleavage of the latter, after orientation of the block copolymer nanodomains by solvent vapor annealing. The resulting porous materials bearing a reactive aldehyde function at the pore surface allowed for further chemical modification via reductive amination with amino-containing compounds, such as tetraethylenepentamine, thus leading to amine-functionalized porous polystyrene. In situ generated gold nanoparticles could then be immobilized within such functionalized porous nanoreactors, and these hybrid materials could find interesting applications in heterogeneous supported catalysis. In this regard, model catalytic reactions, including C-C homocoupling of benzeneboronic acid derivatives, hydride-mediated reduction of nitroaromatic compounds, and especially unprecedented "one-pot" cascade reactions consisting of the latter consecutive reactions from 3-nitrobenzeneboronic acid, were successfully monitored by different chromatographic and spectroscopic techniques.