In the production of commercial Li-ion batteries, the active materials slurries are generally prepared using polyvinylidene fluoride (PVdF) as binder because of its good adhesion properties and electrochemical stability. Unfortunately, there are some disadvantages related to the use of PVdF: the most important is the use of toxic and environmentally unfriendly solvents, such as N-methyl-pyrrolidone (NMP), and the second is the high costs. In the light of these considerations, it seemed straightforward to investigate the suitability of some water-soluble, inexpensive, and eco-friendly materials to test as alternative binders (sodium alginate, chitosan tragacanth gum, gelatin). The rheological properties of these materials have been investigated in addition to the electrochemical characterization. Furthermore, graphite electrodes with PVdF, carboxymethyl cellulose (CMC), and styrene-butadiene rubber (SBR) binders have been considered for sake of comparison. We found that some of these water-soluble binders, besides good electrochemical performances, showed a high adhesion to the current collector and a good electrochemical stability under the experimental conditions employed, which makes them interesting for the next generation of Li-ion batteries.

The present work aims to compare and evaluate the behavior of platinum catalysts supported on different ordered mesoporous carbons (Pt/OMCs). OMCs were templated from two kinds of ordered mesoporous silicas (2-D SBA-15 and 3-D SBA-16), with sucrose as carbon precursor and boric acid as a pore expanding agent. Structural characterizations revealed that all OMCs inherited the structure from silica templates. OMC synthesized from a mixture of sucrose and boric acid exhibited a larger pore size. According to XRD, TEM, and XPS analysis, particle size and distribution of Pt were influenced by the porosity of OMC supports. In single PEMFC tests, catalysts supported on OMC with a 3-D pore structure (Pt/C16sucr: 0.57 W cm–2 at 0.45 V) or with 2-D larger pores (Pt/C15sucr+B: 0.44 W cm–2 at 0.45 V) significantly enhanced the FC performance compared to Pt/C15sucr (0.29 W cm–2 at 0.45 V), which may be attributed to a better mass transfer and a higher catalytic activity. In particular, it was found that Pt/C16sucr had a catalytic behavior superior to that of the Pt/Vulcan commercial catalyst in the high potential region, suggesting that C16sucr is a promising catalyst support for PEMFC application.

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Preliminary results on Pt‐based electrocatalysts prepared with CMK3 mesoporous carbons are presented. The electro‐catalytic performance towards the oxygen reduction reaction (ORR) was compared to that of commercial Pt/C‐Vulcan catalysts with the same Pt content. Polarisation tests were carried out with a single PEM fuel cell containing the Pt/OMC cathodes. The analysis of these tests, based on a semi‐empirical determination of the various polarisation terms, showed an interesting catalytic activity for ORR for the cathodes prepared with mesoporous carbon supports. The preliminary results indicate some critical aspects which need further investigation to improve the ohmic resistance limitation of these materials. Particularly, the variation of the grain size distribution with the Pt content and the effective distribution of Nafion® on the OMC surface should be considered.

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