title: Insights into the effects of functional groups on carbon nanotubes for the electrooxidation of methanol.
abstract: Functionalized carbon nanotubes were used as a support for PtCo nanoparticles. Their performance as electrocatalysts for the electrooxidation of methanol was evaluated by cyclic voltammetry and in situ FTIR reflectance spectroscopy. The onset potentials for both the electrooxidation of methanol and the production of CO(2) shifted to less positive values for catalysts prepared with more oxygen groups on the support. Furthermore, the production of CO(2) was higher on catalysts prepared with functionalized carbon nanotubes. The functional groups play two different but complementary roles. On the one hand, they help to stabilize smaller PtCo particles of ca. 3 nm. On the other hand, they provide the -OH groups necessary for the total oxidation of methanol to CO(2) at potentials less positive than on nonfunctionalized supports. Remarkably, the consumption of carboxylic acid groups along with the production of water is observed in the infrared spectra of the functionalized supports recorded during the electrooxidation of methanol. This observation suggests that the -OH groups of the support can also react with methanol, forming water and an ester.
authors: Dpto. Química-Física Aplicada, Facultad de Ciencias, Universidad Autónoma de Madrid (UAM), C/Francisco Tomás y Valiente 7, 28049 Madrid, Spain.
authors: Patricia
authors: P
authors: Hernández-Fernández
authors: Steve
authors: S
authors: Baranton
authors: Sergio
authors: S
authors: Rojas
authors: Pilar
authors: P
authors: Ocón
authors: Jean-Michel
authors: JM
authors: Léger
authors: Jose Luis G
authors: JL
authors: Fierro