Abstracts Book - IMRC 2018

• SC1-P010
SYNTHESIS OF Sn@Pt/C CORE-SHELL NANOCATALYSTS BY THE
BAE AND POLYOL METHODS FOR THE ETHYLENE GLYCOL
ELECTRO-OXIDATION REACTION
Gerardo Hernández Vázquez 1 , Samuel Dessources 2 , Ivonne Alonso Lemus 3 , Beatriz Escobar 4 ,
Edilso Reguera 5 , Javier Rodriguez Varela 2,6
1 Centro de Investigación y de Estudios Avanzados del IPN - CINVESTAV, Unidad Saltillo, Mexico.
2 Centro de Investigación y de Estudios Avanzados del IPN - CINVESTAV, Programa de
Nanociencias y Nanotecnología, Mexico. 3 CONACYT, Cinvestav Unidad Saltillo, Sustentabilidad
de los Recursos Naturales y Energia, Mexico. 4 CONACyT, Centro de Investigación Científica de
Yucatán (CICY), Unidad de Energía Renovable, Mexico. 5 Centro de Investigación en Ciencia
Aplicada y Tecnología Avanzada, Legaría, IPN, Unidad Legaría, Mexico. 6 Centro de Investigación
y de Estudios Avanzados del IPN - CINVESTAV, Programa de Sustentabilidad de los Recursos
Naturales y Energía, Mexico.
Current challenges in the use of Pt-based core-shell nanostructures for the
catalysis of electrochemical reactions in Direct Alcohol Fuel Cells (DAFCs) are
closely related to their physicochemical properties, which are associated to the
method of synthesis selected. Besides a high catalytic activity, the oxidation of
organic molecules (methanol, ethanol, ethylene glycol) requires core-shell
nanocatalysts with high tolerance to reaction intermediates. This property may
be promoted by the synergistic effect between the core and the shell materials.
Several methods of synthesis have been studied over the last years, such as
impregnation-reduction, precipitation, microemulsion, polyol and Bromide
Anion Exchange (BAE). Some of the objectives during the synthesis of
nanocatalysts are to the particle size growth, to homogeneously disperse
nanoparticles over the carbon support and to control the morphology by
covering the core material by a shell of the second element. Such characteristics
are of interest to obtain nanocatalysts with high catalytic activity. In this work,
Sn@Pt/C core-shell nanostructures have been synthesized by two methods: i)
polyol, where ethylene glycol is used as a solvent and reducing agent (labelled
as Sn@Pt/C-P), ii) BAE, using KBr as solvent and NaBH4 as reducing agent
(Sn@Pt/C-B). The nanocatalysts have been characterized by TEM, XRD and SEM-
EDS. Their catalytic activity has been evaluated for the Ethylene Glycol Oxidation
Reaction (EGOR) in 0.5 mol L -1 H2SO4. The Sn@Pt/C-P nanocatalyst generates a
mass current density (382.75 mA mgPt -1 ) 2.3 and 1.96 times higher than those of
Sn@Pt/C-B and Pt/C, respectively. In terms of specific activity, Sn@Pt/C-B delivers
the highest current density (0.99 mA cmr -2 ), 1.3 and 4.5 times higher than
Sn@Pt/C-P and Pt/C, respectively. Overall, Sn@Pt/C-P promotes the EGOR at