Artigo de peri??dico
Catalysts for fuel cell: production and characterization
Catalisadores para c??lulas a combust??vel: produ????o e caracteriza????o
Registro en:
1516-2893
1
11
Autor
FRANCO, EGBERTO G.
LINARDI, MARCELO
Resumen
Fuel cells technology is one of the most promising
technologies for this century to deal with energy
sustainability. In order to improve fuel cells
performances the search for new electrocatalysts has
a great importance in this technology. The colloidal
method was chosen to produce the catalysts because
a good nanocrystal distribution can be obtained. This
method consists in the production of a stable colloid
that will be anchored in the support (carbon black
Vulcan XC 72 R). The catalysts were investigated by
the following techniques: energy dispersive analysis
(EDX), X-rays powder diffraction (XRD), X-rays
photoelectron spectroscopy (XPS), scanning electron
microscopy (SEM), high resolution transmission
electron microscopy (HRTEM) and polarization curves
(Exi). The binary and ternary catalysts systems
synthesized in this work were tested for the oxidation
of hydrogen, H2/CO mixtures (150 ppm of CO),
methanol and ethanol. The catalyst systems produced
by the colloidal method presents a highly-dispersed
nanocrystals structure with an average size of 2.0 to
3.1 nm. The electrocatalytic activity of the synthesized
Pt-Ru-Mo catalysts for reformate and methanol
oxidation was evidenced by polarization curves showing
a very promising system to be optimized. PtRuDy
behavior is compared to state of the art catalysts for
direct ethanol fuel cells (DEFC) and should be tested
in long term experiments in direct ethanol fuel cells.
Only both structural and electrochemical
characterization together will result in a detailed
understanding of the effect of the structure on the
eletrocatalytic activity of catalysts in real fuel cell
systems. This work is part of a systematic research of
the fuel cell group of IPEN/CNEN-SP and further
investigations in the performance of these catalysts
will be done. The PtRuMo system could be used for
technical applications.