Ethanol electro-oxidation in an alkaline medium using Pd/C, Au/C and PdAu/C electrocatalysts prepared by electron beam irradiation

Carbon-supported Pd, Au and bimetallic PdAu (Pd:Au 90:10, 50:50 and 30:70 atomic ratios) electrocatalysts were prepared using electron beam irradiation. The obtained materials were characterized by energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD) and transmission electron microscopy (TEM), and their catalytic activities toward ethanol electro-oxidation were evaluated in an alkaline medium using electrochemical techniques, in situ attenuated total reflectance Fourier transformed infrared spectroscopy (ATR-FTIR) analysis and a single alkaline direct ethanol fuel cell (ADEFC). EDX analyses showed that the actual Pd: Au atomic ratios were very similar to the nominal ones. X-ray diffractograms of PdAu/C electrocatalysts evidenced the presence of Pd-rich (fcc) and Au-rich (fcc) phases. TEM analysis showed a homogeneous dispersion of nanoparticles on the carbon support, with an average size in the range of 3-5 nm and broad size distributions. Cyclic voltammetry (CV) and chronoamperometry (CA) experiments revealed the superior ambient activity toward ethanol electro-oxidation of PdAu/C electrocatalysts with Pd: Au ratios of 90:10 and 50:50. In situ ATR-FTIR spectroscopy measurements have shown that the mechanism for ethanol electro-oxidation is dependent on catalyst composition, leading to different reaction products, such as acetaldehyde and acetate, depending on the number of electrons transferred. Experiments on a single ADEFC were conducted between 50 and 900 C, and the best performance of 44 mW cm-2 in 2.0molL-1 ethanol was obtained at 850C for the Pd:Au 90:10 catalysts. This superior performance is most likely associated with enhancement of ethanol adsorption on Pd, oxidation of the intermediates, the presence of gold oxide-hydroxyl species, low mean particle diameters and better distribution of particles on the support. © 2013 Elsevier Ltd. All rights reserved.

Synthesis, cytotoxic activity and DNA interaction of Pd(II) complexes bearing N′-methyl-3,5-dimethyl-1-thiocarbamoylpyrazole

A new series of complexes of general formulae [PdX2(tmdmPz)] {X = Cl (1), Br (2), I (3), SCN (4); tmdmPz = N′-methyl-3,5-dimethyl-1- thiocarbamoylpyrazole} have been synthesized and characterized by elemental analysis, molar conductivities, IR, 1H and 13C{ 1H} NMR spectroscopy. In these complexes, the tmdmPz coordinates to Pd(II) center as a neutral N,S-chelating ligand. The geometries of the complexes have been optimized with the DFT method. Cytotoxicity evaluation against LM3 (mammary adenocarcinoma) and LP07 (lung adenocarcinoma) cell lines indicated that complexes 1-4 were more active than cisplatin. The binding of the complexes with a purine base (guanosine) was investigated by 1H NMR and mass spectrometry, showing that the coordination of guanosine occurs through N7. Electrophoretic DNA migration studies showed that all of them modify the DNA tertiary structure. © 2013 Elsevier Ltd. All rights reserved.

Stem cell factor estimula células da musculatura lisa da traqueia a produzir TGF-β, FGF-2 E CCL3/MIP-1α

Pós-graduação em Ciências Fisiológicas - FOA

Estudo eletroquímico da liga de Co-Pd obtidos por eletrodeposição

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Desenvolvimento e teste de nanocatalisadores a base de Pd para a redução de oxigênio

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Investigação das potencialidades de complexos pirazólicos de Pd (II) no desenvolvimento de novas metalo-drogas

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Complexos triazólicos de Pd(II): síntese, caracterização e atividade biológica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Espécies moleculares e supramoleculares de Pd(II) contendo ligantes N,S doadores: síntese e caracterização

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo dos mecanismos envolvidos na expressão de fator de crescimento de células progenitoras e fator de crescimento para fibroblastos-2 por odontoblastos estimulados por lipopolissacarídeos via p42/44, p38 e PI3K

Pós-graduação em Ciência Odontólogica - FOA

Avaliação da correlação entre peroxidação lipídica e o perfil de marcadores inflamatórios em pacientes com Diabetes mellitus tipo 2, dislipidemia e periodontite crônica

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efeito do tratamento periodontal não-cirúrgico em pacientes portadores de Diabetes mellitus tipo 2 com doença periodontal: análises clínica, enzimática e microbiológica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Espécies moleculares e supramoleculares de 'PD'(II)' com ligantes mono, bi e polidentados : caracterização estrutural e atividades biológicas

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Compostos de Pd(II) contendo ligantes piridinicos: potencialidades biologicas e aspectos estruturais

Pós-graduação em Química - IQ

Novos complexos de 'PD'(II): síntese, caracterização e efeito dos ligantes na citotoxicidade e interação com DNA

Pós-graduação em Química - IQ

Síntese, caracterização e avaliação da citotoxicidade de complexos de Pd(II) contendo ligantes fosfínicos de N,S - quelantes

Pós-graduação em Química - IQ