RODRIGO FERNANDO BRAMBILLA DE SOUZA

RODRIGO FERNANDO BRAMBILLA DE SOUZA

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Partial oxidation of methane and generation of electricity using a PEMFC
2019 - NANDENHA, J.; PIASENTIN, R.M.; SILVA, L.G.M.; FONTES, E.H.; NETO, A.O.; SOUZA, R.F.B. de
The aim of this work was to produce methanol through partial oxidation of methane. The gas fed in a solid membrane reactor- PEM fuel cell type (H2/H2O2 + CH4) has been used for electrosynthesis of methanol at room temperature, with electricity cogeneration as a benefit. It was observed that the current density measured when injected CH4 in the cathode decreased about 45%. This occurs due to the conversion of methane inmethanol in some ranges of potentials. In the other hand, in lower ranges of cell potential, formaldehyde was found. In this work, methane was injected on the cathode together with H2O2 solution, where it was observed that the catalytic layer adsorbed CH4 and H2O2 in active sites, which produced OH− radicals that reacted with the hydrocarbon.
Glycerol oxidation reaction using PdAu/C electrocatalysts
2016 - OTTONI, CRISTIANE A.; SILVA, SIRLANE G. da; SOUZA, RODRIGO F.B. de; OLIVEIRA NETO, ALMIR
Ethanol electrooxidation on PdIr/C electrocatalysts in alkaline media: electrochemical and fuel cell studies
2015 - NETO, A.O.; SILVA, S.G. da; BUZZO, G.S.; SOUZA, R.F.B. de; ASSUMPCAO, M.H.M.T.; SPINACE, E.V.; SILVA, J.C.M.
PdIr/C electrocatalysts in different atomic ratios (Pd:Ir 90:10, 70:30, and 50:50), Pd/C and Ir/C supported on Vulcan XC 72 carbon were tested for ethanol electrooxidation in alkaline media. The electrocatalysts were prepared by borohydride reduction method. The electrocatalysts were characterized by Xray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), cyclic voltammetry (CV), and chronoamperometry (CA). The XRD measurements suggested the PdIr alloy formation. EDS analyses showed the real atomic ratios similar to the nominal ones. TEM showed the average particle diameter between 4.6 and 5.8 nm for all compositions prepared. The catalytic activity for ethanol electrooxidation in alkaline medium investigated by CV and CA at room temperature showed that PdIr/C (90:10) exhibited higher performance for ethanol oxidation in comparison with others PdIr/C compositions, Pd/ C and Ir/C, while the experiments on a single direct ethanol alkaline fuel cell at 70 °C showed higher performance for PtIr (70:30). The best results obtained using PdIr/C electrocatalysts may be associated to the electronic effect between Pd and Ir that might cause a decrease of poisoning on catalyst and the occurrence of bifunctional mechanism.
Effect of the TiOsub(2) content as support with carbon toward methanol electro-oxidation in alkaline media using platinum nanoparticles as electrocatalysts
2014 - SILVA, J.C.M.; SOUZA, R.F.B. de; BUZZO, G.S.; SPINACE, E.V.; OLIVEIRA NETO, A.; ASSUMPCAO, M.H.M.T.
Preparation of PdAu/C-Sbsub(2)-SnOsub(2) electrocatalysts by borohydride reduction process for direct formic acid fuel cell
2013 - NANDENHA, J.; SOUZA, R.F.B. de; ASSUMPCAO, M.H.M.T.; SPINACE, E.V.; OLIVEIRA NETO, A.
Pd/C-Sb2O5·SnO2 and PdAu/C-Sb2O5·SnO2 electrocatalysts with different PdAu atomic ratio (90:10, 70:30, and 50:50) were prepared by borohydride reduction method, and characterized by X-ray diffraction, transmission electron microscopy, cyclic voltammetry, chronoamperommetry, and performance test on direct formic acid fuel cell at 100 °C. Xray diffraction showed for Pd/C-Sb2O5·SnO2 the presence of Pd face-centered cubic (fcc) system, while for PdAu/C-Sb2O5·SnO2 it showed the presence of Pd fcc phase, PdAu fcc alloys and a segregated phases fcc Pd-rich and Au-rich phases. TEM micrographs and histograms for all electrocatalysts showed that the nanoparticles where not well dispersed on the support and some agglomerates were present. The electrochemical studies showed that PdAu/C-Sb2O5·SnO2 (70:30) had superior performance for formic acid electro-oxidation at 25 °C compared to others electrocatalysts prepared while PdAu/C-Sb2O5·SnO2 (90:10) showed superior performance in direct formic acidic fuel cell at 100 °C. These results indicated that the addition of 10–30 % Au to Pd favor the electro-oxidation of formic acid. This effect could be attributed to the synergy between the constituents of the electrocatalyst (metallic Pd and Au, SnO2, and Sb2O5·SnO2).