Carbon xerogels as supports for catalysts and electrocatalysts

Conference (2009, June 14)

Degradation mechanisms of Pt/C electrocatalysts at the nm-scale

Conference (2009, May 24)

Synthesis of very highly dispersed platinum catalysts supported on carbon xerogels by the strong electrostatic adsorption method

in Journal of Catalysis (2009), 261

Highly dispersed Pt/carbon xerogel catalysts are obtained by applying the “Strong Electrostatic Adsorption” (SEA) of hexachloroplatinic acid to carbon xerogels (PZC = 9.4) and platinum tetraammine ... [more ▼]

Highly dispersed Pt/carbon xerogel catalysts are obtained by applying the “Strong Electrostatic Adsorption” (SEA) of hexachloroplatinic acid to carbon xerogels (PZC = 9.4) and platinum tetraammine chloride to oxidized carbon xerogels (PZC = 2.4). After the reduction step, all these Pt/carbon xerogel catalysts display a very high level of metal dispersion: very small platinum particles (1.1-1.3 nm) are observed by TEM. Pt particle sizes obtained by CO chemisorption are in good agreement with TEM micrographs, which shows that the metal is accessible to reactants. These Pt/carbon xerogel catalysts are very active for the hydrogenation of benzene into cyclohexane. [less ▲]

Study of diffusive limitations in Proton Exchange Membrane Fuel Cells (PEMFC)

in Proceedings of the International Carbon Conference 2009 (2009)

EDLC electrodes from cellulose-based carbon aerogels : influence of the carbon's surface chemistry

in Proceedings of the International Carbon Conference 2009 (2009)

Electrochemical characterization of Pt/carbon xerogel and Pt/carbon aerogel catalysts - first insights into the influence of the carbon texture on the Pt nanoparticles morphology and catalytic activity

in Journal of Materials Science (2009), 44

Silo flow-pattern diagnosis using the tracer method

in Journal of Food Engineering (2009), 91(1), 118-125

The storage silo of a sugar refinery was designed by its manufacturer for a plug-flow pattern of sugar ingots in order to ensure effective drying of the sugar introduced at the top of the silo. Because of ... [more ▼]

The storage silo of a sugar refinery was designed by its manufacturer for a plug-flow pattern of sugar ingots in order to ensure effective drying of the sugar introduced at the top of the silo. Because of the excessive moisture content of the extracted ingots, the quality of flow within the silo was called into question. The silo flow-pattern was thus studied by introducing sugar lumps as a tracer at the top of the silo filled with ingots. The tracer weight percentage was measured at the outlet. Results show that the silo flow-pattern is not of the plug-flow type in its whole volume: after formation of a crater, only the central volume flows, while the outer residual volume remains motionless. The tracer test also enabled the detection of preferential flow patterns. The tracer method was found to be quite useful as a diagnosis method for such a device in normal functioning. (C) 2008 Elsevier Ltd. All rights reserved. [less ▲]

Highly loaded Pt/carbon xerogel catalysts for PEM fuel cells by the Strong Electrostatic Adsorption Method

Poster (2008, November 09)

Studying the chemical activation in carbon xerogels

Poster (2008, September 08)

Effect of the counter-ion of the basification agent on the pore texture of organic and carbon xerogels

in Journal of Non-Crystalline Solids (2008), 354(40-41), 4698-4701

Organic and carbon xerogels were prepared by polycondensation of resorcinol with formaldehyde in water, followed by evaporative drying and, eventually, pyrolysis. The pH of the precursor's solution was ... [more ▼]

Organic and carbon xerogels were prepared by polycondensation of resorcinol with formaldehyde in water, followed by evaporative drying and, eventually, pyrolysis. The pH of the precursor's solution was fixed at 6.0 in all cases by adding various hydroxides as basification agent. Three alkali metal hydroxides (LiOH, NaOH and KOH) and three alkaline earth metals hydroxides (Ca(OH)(2), Ba(OH)(2), Sr(OH)(2)) were used. It was found that the pore texture of the organic and carbon xerogels is totally independent on the cation size, but depends on the charge and concentration of the counter-cation. Indeed, the pore size of the alkaline earth metal loaded samples is larger than that of the alkali metal-doped xerogels. As a matter of fact, to reach the same initial pH, the concentration in alkali metal hydroxide must be twice that of the alkaline earth metal base. The effect of ions on the pore texture was thus attributed to electrostatic effects on the microphase separation process that occurs prior to gelation. (C) 2008 Elsevier B.V. All rights reserved. [less ▲]