David Cardoso

Bipolar Electrochemistry, a Focal Point of Future Research

Bipolar electrochemistry is a conventional method based on the polarization of an isolated substrate under an applied electric field. This technique has been applied to electrolysis, corrosion, and other areas of chemical engineering since the twentieth century. However, it has been recognized as a powerful tool in many modern domains after water splitting has been demonstrated to be possible using micrometer-sized bipolar electrodes. Modifying inorganic objects in novel ways, such as creating electrical contacts between metal particles using directed electrochemical growth or shaping and exploring the micro- and nanoworld are some of the new applications in this field. Fabrication of electronic devices, electroanalytical purposes, generation of molecular and material gradients, functionalization of single micro- and nanopores, synthesis of Janus particles, design of swimmers, and asymmetric modification of nanoparticles will be discussed in this article as a focal point of future research in bipolar electrochemistry.

Hydrogen evolution on nanostructured Ni-Cu foams

Three-dimensional (3D) nickel–copper (Ni–Cu) nanostructured foams were prepared by galvanostatic electrodeposition, on stainless steel substrates, using the dynamic hydrogen bubble template. These foams were tested as electrodes for the hydrogen evolution reaction (HER) in 8 M KOH solutions. Polarisation curves were obtained for the Ni–Cu foams and for a solid Ni electrode, in the 25–85 °C temperature range, and the main kinetic parameters were determined. It was observed that the 3D foams have higher catalytic activity than pure Ni. HER activation energies for the Ni–Cu foams were lower (34–36 kJ mol−1) than those calculated for the Ni electrode (62 kJ mol−1). The foams also presented high stability for HER, which makes them potentially attractive cathode materials for application in industrial alkaline electrolysers.

On the performance of commercially available corrosion-resistant nickel alloys: a review

Abstract The corrosion behavior of nickel (Ni)-based alloys used for low-temperature aqueous or condensed systems is reviewed in detail in this paper. Commercially available pure Ni, nickel-copper (Ni-Cu), nickel-molybdenum (Ni-Mo), nickel-chromium-molybdenum (Ni-Cr-Mo), and nickel-chromium-iron (Ni-Cr-Fe) alloys as well as cast Ni-based alloys are addressed. It is shown that Ni-Cr-Mo alloys are multipurpose alloys that can be used in both reducing and oxidizing conditions. Special attention is given to a few Ni alloys, which not only extend the range of usefulness of existing alloys by overcoming their limitations but are also reliable and cost-effective and have opened new areas of applications.