Sugarcane molasses as a pseudocapacitive material for supercapacitors

Oxygen-rich carbons were obtained from sugarcane molasses by two methods: direct carbonisation on one hand, and hydrothermal carbonisation and subsequent pyrolysis on the other hand. As no activation treatments were applied, the porous texture was poorly developed and mainly composed of ultramicropores with restricted access to electrolyte ions. Despite this, the directly carbonised molasses exhibited specific capacitances up to 153 F g−1 at 0.5 mV s−1 in 1 M H2SO4 electrolyte when tested as electrodes in a three-electrode system. Given the low specific surface areas of the carbons, the capacitance values were mainly assigned to their pseudocapacitance contributions. The latter were more adequately estimated by considering the NLDFT surface area (SNLDFT) than the BET area (ABET) due to the narrow porosity of the materials. Maximum values of pseudocapacitance contribution of 35.2% were attained for the carbon with a SNLDFT of 178 m2 g−1, which were explained by the high concentrations of surface oxygen groups, such as quinones and carbonyls.The IJL research team gratefully acknowledges the financial support of the CPER 2007-2013 "Structuration du Pôle de Comeptitivité Fibres Grand'Est" (Competitiveness Fibre Cluster), through local (Conseil Général des Vosges), regional (Région Lorraine), national (DRRT and FNADT ) and European (FEDER) funds. Part of this work was supported by CHEERS project (FEDER funds). Dr. A. Sanchez-Sanchez aknowledges the University of Lorraine and the Region Lorraine for financing her post-Doctoral contract.Peer reviewe

Le bien-être des écoliers

Cet ouvrage propose un travail pluridisciplinaire d’exploration de la question de l’expérience de bien-être et/ou de mal-être des élèves en proposant de revenir au singulier, à l’intime, à la qualité d’être, à la vie humaine et à sa difficile recherche de sens. La question du bien-être étant en effet très idéologisée aujourd’hui, les auteurs ont uni leurs efforts pour penser cette question « à hauteur d’enfant ». L’insertion d’interchapitres ajoute ainsi des illustrations concrètes aux préoccupations plus théoriques de certaines analyses. Un lexique des concepts principaux est disponible en fin d’ouvrage pour aider le lecteur à se repérer dans les différents sens des concepts de bien-être, de qualité de vie, etc