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Lead sulfide (PbS) thin films were grown on a single crystal Ag(111) substrate by Electrochemical Atomic Layer Epitaxy (ECALE) method, i.e., by alternated underpotential deposition (UPD) of lead and sulfur. The electrochemical analysis includes the investigation of the underpotential deposition processes of both Pb and S, and the characterization of deposits obtained with different deposition cycles to confirm the attainment of the right stoichiometric ratio between Pb and S. The morphological analysis has been performed by Atomic Force Microscopy (AFM) for deposits formed with 50 and 75 deposition cycles and at different times of exposition to the atmosphere.

(GDLs), such as control the water balance in the membrane electrode assembly (MEA), allow suitable gas permeability and porosity, etc. Aware of the GDL importance in the cell performance and its great demand in scale-up projects, the fuel cell research group at Instituto de Pesquisas Energéticas e Nucleares (IPEN) has developed a Sieve Printing method (innovative in Brazil) as a strategic solution for producing GDL and electrodes used in high power PEMFC stacks. The method has shown to be adequate to fabricate low cost electrodes, GDLs of different dimensions and to produce any amount of MEAs for power stacks.

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The Cu/Pd bimetallic system electrodeposited on boron-doped diamond (BDD) films for application, as electrode material in the electrochemical reduction of nitrate was studied. The electrochemical behavior of Cu, Pd, and Cu/Pd bimetallic system was evaluated by cyclic voltammetry. From these results, the formation of the Cu/Pd composite was verified. In addition, Cu with different phases and a Cu/Pd phase in the composite were obtained. Morphological analysis by scanning electron microscopy (SEM) revealed a homogeneous distribution of Cu/Pd bimetallic particles with intermediary dimensions compared to those observed in Cu or Pd electrodeposits separately. These composites were tested as electrocatalysts for nitrate reduction in Britton-Robinson buffer solution (pH 9). Electrochemical measurements showed that composites with higher Cu content displayed the best electrocatalytic activity for nitrate reduction, and the Cu/Pd phase in the bimetallic system served to improve the Cu adherence on BDD electrode.