Jean-Yves Huot

Low Hydrogen Overpotential Nanocrystalline Ni‐Mo Cathodes for Alkaline Water Electrolysis

Nanocrystalline fcc Ni x Mo 1−x (x=0.60, 0.85 atom percent) metallic powders prepared by high energy mechanical alloying were found to possess electrocatalytic activities for the hydrogen evolution reaction in 30 weight percent KOH at 70°C equivalent to that of the best electrocatalysts. The formation process and the structural properties of these nanocrystalline alloys were investigated. The active phase is a metastable solid solution of Mo in fcc Ni whose electrocatalytic activity is associated with the reduction in the size of the crystallites and correlates with the expansion of the Ni lattice

A comprehensive thermodynamic investigation of water-ethylene glycol mixtures at 5, 25, and 45°C

A detailed thermodynamic study of water (W)-ethylene glycol (EG) mixtures has been carried out as function of temperature (5, 25 and 45°C) and over the entire composition range. The data comprise heats of mixing, densities, heat capacities and compression coefficients. Using excess free energy data from earlier work, molar excess functions were calculated for free energies GE, enthalpies HE and entropies TSE, volumes VE, isobaric and isochoric heat capacities CPE, CVE, adiabatic and isothermal compression KE, KTE and thermal expansion EE, as well as the temperature derivatives of K, C and E functions. The corresponding partial molar quantities were also calculated except for G, H and S and are reported for both EG and W. Also calculated were cohesive energy density, internal pressure and Kirkwood-Buff integrals. The data reported here for EG-W mixtures are compared with similar data for other mixtures as available in order to gain insight into: 1) the relative discriminating ability of various thermodynamic coefficients towards weak cooperative intermolecular interactions in liquids; 2) the quantitative similarities and differences between liquid water and ethylene glycol; 3) the intermolecular phenomena which dominate the properties of EG-W mixtures of varying composition; 4) the usefulness of a qualtitative description of liquid water proposed by Lumry et al. which involves hydrogen-bonding interactions, hydrogen-bonding connectivity and small cooperative fluctuation units.

Electrochemical and Electrocatalytic Behavior of an Iron‐Base Amorphous Alloy in Alkaline Solutions at 70°C

An alloy exhibiting high electrocatalytic activity for the hydrogen evolution reaction (HER) has been prepared by anodic oxidation of amorphous Fe 60 Co 20 Si 10 B 10 in 30 weight percent (w/o) KOH at 70 o C

Thermodynamic properties of naphthalene and uric acid in ethylene glycol-water mixtures

The solubility of naphthalene and uric acid was measured as function of temperature (5–45°C) in water(W)-ethylene glycol(EG) mixtures over the entire composition range. The molar solubility data were used to calculate transfer Gibbs energies ΔGtr0(W→W-EG) (from water to water-ethylene glycol mixtures) and the temperature dependence of ΔG0 was used to compute the corresponding transfer enthalpies and heat capacities. The thermodynamic quantities are interpreted in terms of two contributions; a cavity term which is estimated using the scaled particle theory (SPT) and a solute-solvent interaction term. The latter is inferred from comparisons involving the SPT results and the naphthalene data, or the data for naphthalene and uric acid. The solvation effects in W-EG mixtures are discussed with reference to thermodynamic properties of the solvent mixtures available from previous work.