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In the present work, copper species were incorporated in SBA-15 organized mesoporous silica (“OMS”) through wet impregnation of copper nitrate and the corresponding material was evaluated as SO 2 adsorbent. The calcination under a high flow of synthetic air leads to the formation of highly dispersed copper species in strong interaction with the support (Cu 2 + O Si). Indeed, the characterization of this material by X-Ray Diffraction (XRD) and Transmission Electron Microscopy (TEM), do not indicate the presence of crystalline CuO. A comprehensive X-ray Photoelectron Spectroscopy (XPS) study allowed the identification of the active species in SO x trapping and underlined the importance of a thermal pretreatment on the performances of the adsorbent in SO x trapping. It reveals that a pretreatment at 600 °C leads to the formation of active Cu + species in higher amount ([Cu + ] = 79.0%) than at 400 °C ([Cu + ] = 37.6%), which strongly increases the adsorbent efficiency. These species were found to be stable in the presence of [O 2 ] = 10% (balance nitrogen) at 400 °C but unstable at ambient atmosphere at room temperature (presence of water). The treatment under SO 2 at 400 °C leads to the reoxidation of the Cu + species into Cu 2 + ones, which are partially sulfated (formation of CuSO 4 ). Additionally, the sulfation step causes the sintering of a part of the Cu 2 + O Si species into CuO. A reaction scheme was proposed according to which, in a first step Cu + species catalyze the SO 2 oxidation to SO 3 . In the second step, Cu(I) is reoxidized into Cu(II) as CuSO 4 . [ABSTRACT FROM AUTHOR]

Abstract A fast, simple and environmentally friendly one-pot route to obtain carbon/SiO 2 hybrid materials is reported in this work. This consists in simple mixture of carbon and silica precursors, followed by thermal annealing at different temperatures. An interpenetrating hybrid network composed of hard carbon and amorphous SiO 2 nanoparticles (2–5 nm) homogeneously distributed was achieved. Increasing the annealing temperature from 600 °C up to 1200 °C, the material porosity and oxygen functional groups are gradually removed, while the amorphous nature of SiO 2 is conserved. This allows to diminish the irreversible capacity during the first charge-discharge cycle and to increase the reversible capacity. An excellent cycling capability, with a reversible capacity up to 535 mA hg-1 at C/5 constant current rate was obtained for C/SiO 2 materials used as anodes for Li-ion batteries. An atypical increase of the capacity during the first 50 cycles followed by a stable plateau up to 250 cycles was observed and related to electrolyte wettability limitation through the materials, particularly for those annealed at high temperatures which are more hydrophobic, less porous and the SiO 2 nanoparticles less accessible. The SiO 2 lithiation mechanism was evaluated by XRD, TEM and XPS post-mortem analyses and revealed the formation of reversible lithium silicate phases. Graphical abstract A green one-pot route to obtain carbon/SiO 2 hybrid materials with high capacity for Li-ion batteries is reported. Image 1 [ABSTRACT FROM AUTHOR]

Sulfur-doped porous carbons were synthesized by two synthetic approaches, i.e. a direct one (soft-template) and an indirect one (hard-template). In the soft-template approach, a phenolic resin based on phloroglucinol or resorcinol and thiophene carboxaldehyde (TCA) was self-assembled with a triblock copolymer followed by carbonization in inert atmosphere. For the second method, zeolite beta was used as hard-template and infiltrated with carbon by chemical vapor deposition (CVD) process followed by H 2 S treatment. Mesoporous materials with uniform pore size and moderate apparent specific surface area (up to 635 m 2 g −1 ) were obtained by soft-template route. The hard-template route, coupled with H 2 S post-treatment, allowed to obtain highly microporous/mesoporous materials having high apparent surface area (1700–2500 m 2 g −1 ) and high total pore volume (1.25–1.95 cm 3 g −1 ). High temperature or amounts of TCA induce a decrease of the microporosity and apparent surface area while the mesoporosity varies distinctly depending on the synthesis method used. The sulfur content could be easily modified by the amount of thiophene carboxaldehyde for the soft-templating route (up to 10.9 wt % at 600 °C) or by the H 2 S heat-treatment temperature for the hard-templating method. In the latter case, with the increase of the temperature up to 900 °C, high S-content was reached (up to 14.4 wt %). The influence of the carbon porosity and surface functionality on the H 2 and CO 2 adsorption was evaluated. Hard-templated carbons possessing well developed microporosity adsorb the highest amounts of H 2 and CO 2 . The sulfur and oxygen groups lead to improvement of the hydrogen adsorption capacity and have less significant effect on CO 2 storage. [ABSTRACT FROM AUTHOR]

Abstract: Junctions between aluminium substrates and ethylene-co-propylene-co-diene terpolymer (EPDM) have been strengthened by depositing alkene functionalized plasma polymers on the aluminium side. The double bonds in the plasma polymer layer were able to covalently bond to the EPDM during the crosslinking step with peroxide. Variations in the peel strength were observed by varying of the plasma duty cycle during plasma polymer deposition. The higher peel strength was obtained with low duty cycles. Analysis of the failure after peel tests showed a cohesive rupture in the EPDM substrate. The differences were explained by analysing the respective concentration of alkene groups in the plasma polymer layer. [Copyright &y& Elsevier]

Abstract: The preparation of cheap nitrogen-enriched materials with large adsorptive capacities and selectivity towards volatile organic compounds remains a challenge. Ammoxidation has been used to prepare nitrogen-enriched activated carbons using a demineralised Polish lignite. The lignite samples were demineralised by two different methods before nitrogen-enrichment by ammoxidation and physical activation in steam. The surface chemistry was investigated by elemental analysis, Boehm titration, infrared and XPS spectroscopies and adsorptive properties by a linear solvation energy relationship approach. Results show a quasi-total demineralisation and a higher reactivity towards nitrogen for the demineralised samples. The BET surface is also higher than for the non-demineralised lignite. Active carbons previously ammoxidated and demineralised are more interesting in terms of selective removal of gaseous pollutants. [Copyright &y& Elsevier]