RODRIGO FERNANDO BRAMBILLA DE SOUZA

RODRIGO FERNANDO BRAMBILLA DE SOUZA

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Direct Alkaline Anion Exchange Membrane Fuel Cell to converting methane into methanol
2019 - SANTOS, MONIQUE C.L.; NUNES, LIVIA C.; SILVA, LUIS M.G.; RAMOS, ANDREZZA S.; FONSECA, FABIO C.; SOUZA, RODRIGO F.B. de; NETO, ALMIR O.
Methane is the main constituent of natural gas and can be converted in higher value-added products for electricity cogeneration. It could be used as a solid membrane reactor (SMR) for application in Alkaline Anion-Exchange Membrane Fuel Cell (AAEMFC). The investigation for the conversion of methane was based on sodium borohydride (NaBH4) method using Pt/C Basf, Pd/C, Ni/C as catalysts. The electrocatalysts were prepared with 20 wt% of metals loading on carbon. The X-ray diffraction (XRD) analysis revealed a face-centered cubic structure (FCC) for Pt/C and Pd/C catalysts, was observed Ni/ NiO phases for Ni/C electrocatalyst. The Transmission Electron Microscopy (TEM) exhibited a good dispersion of nanoparticles and some agglomerations on the support, with a mean size of 6.4 nm for Pd/C, 5.7 nm for Ni/C and near to 2 nm size for Pt/C. The experiments with AAEMFC showed that all materials can carry out the reaction spontaneously. Pt/C catalyst presents energy density higher than the other materials. FTIR data suggest that methane was converted into small products organic molecules such as methanol and formate in different potentials for Pt/C, Pd/C, and Ni/C. The products were quantified by Raman spectroscopy. The high conversion efficiency obtained was about 20% at 0.3 V using Pt/C catalyst, the maximum conversion over Pd/C was 17.5% at 0.15 V, associated with the formation of a thin layer of PdO on the catalytic surface. The highest conversion rate (13%) was observed in closed circuit potentials to the short circuit in the cell with Ni/C catalyst. The results suggest that for the selective conversion of methane to methanol are most promising using materials containing Pt or Pd.
Microbial fuel cell‑induced production of fungal laccase to degrade the anthraquinone dye Remazol Brilliant Blue R
2019 - SIMÕES, MARTA F.; MAIORANO, ALFREDO E.; SANTOS, JONAS G. dos; PEIXOTO, LUCIANA; SOUZA, RODRIGO F.B. de; OLIVEIRA NETO, ALMIR; BRITO, ANTONIO G.; OTTONI, CRISTIANE A.
The anthraquinone dye Remazol Brilliant Blue R is largely used in the textile industry. However, its removal from wastewaters is costly and complex. Many methods have been tested to solve this ecological problem, but there is still a need for efficient methods. We propose here an alternative use of a two-chambered microbial fuel cell (MFC), fuelled with domestic wastewater in the anodic chamber, to degrade a simulated textile dye effluent made of Remazol Brilliant Blue R inoculated with an immobilised fungal strain, Pleurotus ostreatus URM 4809, as a laccase producer, in the cathodic chamber. The MFC showed continuous synthesis of laccase in the cathodic chamber, which, in turn, promoted the rapid decolourisation, of more than 86% of the textile dye effluent. The yield was further increased by the addition of glycerol. Electrochemical monitoring also indicated an increase in power density and current density. After 20 days of MFC operation, 62.1% of organic matter was removed in the anodic compartment, thus leaving the effluent with a much lower toxicity.
Estudo da oxidação eletroquímica do ácido fórmico em meio alcalino utilizando eletrocatalisadores Pd/C-Sbsub(2)Osub(5)-SnOsub(2) PdAuIr/C-Sbsub(2)Osub(5)SnOsub(2)
2015 - NANDENHA, J.; SOUZA, R.F.B.; SPINACE, E.V.; NETO, A.O.
Eletrooxidação do glicerol em meio alcalino utilizando eletrocatalisadores Pt/C-ITO sintetizados via redução por borohidreto de sódio
2015 - RAMOS, CARLOS E.D.; OTTONI, CRISTIANE A.; SOUZA, RODRIGO F.B. de; OLIVEIRA NETO, ALMIR
Simultaneous electricity generation and Remazol Brilliant Blue Reactive decolourisation in cathode chamber microbial fuel cell
2015 - OTTONI, CRISTIANE; SOUZA, RODRIGO; NETO, ALMIR; BRITO, ANTONIO G.; POCO, JOAO; MAIORANO, JOSE E.
PtAu electrocatalyst for glycerol oxidation reaction using a ATR-FTIR/Single direct alkaline glycerol/Air cell in situ study
2016 - OTTONI, CRISTIANE A.; SILVA, SIRLANE G. da; SOUZA, RODRIGO F.B. de; OLIVEIRA NETO, ALMIR
Different ratios of PtAu/C electrocatalysts were synthesized and assessed for their capability by glycerol electrooxidation. Electrocatalysts were characterized by Xray diffraction (XRD), transmission electron microscopy (TEM), cyclic voltammetry (CV), chronoamperometry, and direct glycerol/air fuel cell coupled with a ATR-FTIR setup. XRD of PtAu/C electrocatalysts showed the presence of Pt (fcc), Au (fcc), and PtAu (fcc) phases, and TEM images for PtAu/C electrocatalysts showed particle size between 5.4 and 5.8 nm. PtAu/C (50:50) presented the best result for glycerol electrooxidation by cyclic voltammetry and chronoamperommetry measurements in comparison with other electrocatalysts prepared. All PtAu/C showed better performance in comparison with Pt/C and Au/C. Moreover, the addition of gold to platinum favored glycerol by electronic effect and bifunctional mechanism. Through ATRFTIR/direct alkaline glycerol/air cell in-situ study, it was possible to identify glycerate and tartronate as main products formed during the electrochemical glycerol oxidation.
Oxidation of ammonia using PtRh/C electrocatalysts: fuel cell and electrochemical evaluation
2015 - ASSUMPCAO, MONICA H.M.T.; PIASENTIN, RICARDO M.; HAMMER, PETER; SOUZA, RODRIGO F.B. de; BUZZO, GUILHERME S.; SANTOS, MAURO C.; SPINACE, ESTEVAM V.; OLIVEIRA NETO, ALMIR; SILVA, JULIO C.M. da
This study reports on the use of PtRh/C electrocatalysts prepared by the borohydride reduction method with different Pt:Rh atomic ratios: (90:10, 70:30 and 50:50) which was investigated toward the ammonia electro-oxidation considering electrochemical and also direct ammonia fuel cell (DAFC) experiments. The DAFC experiments were conducted using different proportions of NH4OH and KOH as fuels. X-ray diffraction showed the formation of PtRh alloy while transmission electron micrographs showed the particles sizes between 4.1 and 4.5 nm. Among the different NH4OH and KOH concentrations the combination of 3 mol L−1 NH4OH and 3 mol L−1 KOH was the most favorable due to the higher KOH concentration, which increased the electrolyte conductivity, thus, improving the ammonia oxidation. Moreover, among the PtRh/C electrocatalysts the Pt:Rh ratio of 90:10 showed to be the best suited one since it showed a power density almost 60% higher than Pt. X-ray photoelectron spectroscopy results revealed for this catalyst that the nanoparticles contain a high proportion of metallic Pt and Rh phases, supporting the alloy formation between Pt and Rh. The improved fuel cell efficiency can be related to the combination of different effects: the alloy formation between Pt and Rh (electronic effect), suppressing the adsorption strength of poisonous intermediates, and a synergic effect between Pt and Rh at this composition.
Amônia: uma nova alternativa para células a combustível alcalinas?
2014 - ASSUMPCAO, MONICA H.M.T.; SILVA, SIRLANE G. da; SOUZA, RODRIGO F.B. de; BUZZO, GUILHERME S.; SPINACE, ESTEVAM V.; NETO, ALMIR O.; SILVA, JULIO C.M. da
Oxidation of small organics molecules mixtures on PtCeO2/C
2011 - SOUZA, R.F.B. de; SILVA, J.C.M.; D'VILLA SILVA, M.; SIMÕES, F.C.; NETO, A.O.; SANTOS, M.C.
Atividade catalítica de nanopartículas de óxido de cério e vânadio para a eletrossíntese de peróxido de hidrogênio
2012 - SOUZA, RODRIGO F.B. de; SILVA, JULIO C.M.; ASSUMPCAO, MONICA H.M.T.; OLIVEIRA NETO, ALMIR; SANTOS, MAURO C. dos