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Carbon materials have rarely been used as support for CO2 methanation, which is usually carried out using catalysts supported on metal oxides. Here, it is shown that Ru nanoparticles supported on nitrogen-doped carbon nanofibers (NCNF) provide competitive CH4 production rate and stability compared to Al2O3-supported catalysts. Contrary to the general belief about the inert nature of carbon supports, it is demonstrated that NCNF is a non-innocent spectator in CO2 methanation due to its ability to store a high amount of COad reaction intermediates. This explains the excellent catalytic behaviour afforded by this unconventional catalyst support. ; The financial support of European Commission (FREECATS project, FP7 Grant agreement nº 280658), from Spanish Ministry MINECO and the European Regional Development Fund (project ENE2013-48816-C5-5-R), and Regional Government of Aragon (DGA-ESF-T66 Grupo Consolidado) are gratefully acknowledged. ; Peer reviewed

El pdf del artículo es la versión post-print. ; Sulfonated hydrothermal carbons present high activity for esterification of palmitic acid with alcohols. However, the catalyst is significantly deactivated upon recovery. Leaching of sulfonated species does not account for this deactivation, which is observed even by pretreatment only with the alcohol under reflux. Solid state NMR shows the presence of chemically bound alkyl groups coming from the alcohol, clearly different from strongly physisorbed species obtained by pretreatment at room temperature. The formation of sulfonate esters accounts for the deactivation behavior in reactions taking place in alcohols as solvents, mainly with methanol due to its higher reactivity. © 2012 Elsevier Inc. All rights reserved. ; This work was made possible by the financial support of Aragón regional government (Project PI050/09), the Spanish Ministerio de Ciencia e Innovación (Projects MAT 2008-02365, CTQ2011-28124), and the European Commission (Grant agreement No. 226347). ; Peer Reviewed

First published online Jan. 16, 2012 ; A well attached coating of nitrogen-functionalised carbon nanofibers (N-CNFs) has been prepared on the walls of cordierite monolith channels. It is formed via concurrent decomposition of ethane and ammonia catalysed by nickel nanoparticles dispersed on alumina coated cordierite monolith. N-CNF/monoliths synthesis employing several growth temperatures and NH 3 compositions was exhaustively characterised by Raman, XPS, elemental analysis and TEM. Synthesis conditions affected profoundly content and type of nitrogen functionality, enabling its fine tuning. N-CNFs surface chemistry and microstructure differed remarkably from its N-free counterparts. ; The authors are grateful to the financial support of the European Commission within the 7th FP (Grant agreement no.: 226347) and of Spanish Government (MAT 2008-02365). ; Peer Reviewed

A bottom-up approach based on hydrothermal carbonization of organic molecules has been used to prepare carbon materials doped with either nitrogen or sulfur or both. To generate mesopores, ZnCl2 has been used as removable structure-directing agent. The final mean pore size depended on the type of dopant element. The doped materials exhibited remarkable activity as electrocatalyst in oxygen reduction reaction with nearly complete selectivity to H2O2 synthesis. N-doped catalyst with an intermediate nitrogen content (4 wt%) and around 80% of pore volume in the mesopore range provided significantly better performance than a catalyst of comparable composition but differing in the porous structure, i.e. 70 % of pore volume in the microporous range. ; The financial support of European Commission (FREECATS project, FP7 Grant agreement nº 280658), from Spanish Ministry MINECO and the European Regional Development Fund (project ENE2013-48816-C5-5-R), and Regional Government of Aragon (DGA-ESF-T66 Grupo Consolidado) are gratefully acknowledged. ; Peer reviewed

El pdf del artículo es la versión post-print ; A hydrothermal carbon layer has been coated on graphite felt using a carbohydrate solution (glucose, sucrose or starch) as precursor. The coating is uniform in thickness and coverage, and exhibits excellent adhesion to the substrate. It is highly hydrophilic, very accessible to reactants and the thickness can be tuned by the synthesis conditions. The coating was functionalized with sulfonic acid groups and its morphology and surface chemistry characterized by SEM, TPO-MS, IR-spectroscopy and XPS. The sulfonated material has been tested in the esterification of palmitic acid with methanol exhibiting significant activity and stability. * ; This work has been possible thanks to the financial support of Aragón regional government (PI050/09), Spanish national government (MAT 2008-02365, CTQ2008-05138, Consolider Ingenio 2010 INTECAT CSD2006-0003) and European Commission (Grant agreement No. 226347). References ; Peer reviewed