Jana Velická

MnOx/C composites as electrode materials II. Reduction of oxygen on bifunctional catalysts based on manganese oxides

Abstract MnO x /C composites prepared by the reduction of KMnO 4 by active carbon black and doped with Ca(II), Mg(II), Ni(II), Bi(III), and Cr(III) ions were tested as catalysts of oxygen reduction in alkaline electrolyte. The polarisation curves were analysed by logarithmic wave analysis. MnO x doped with the transition metal salts are slightly more active than those with Ca(II) and Mg(II).

Hydrogen evolution and hydrogen sorption on amorphous smooth MeP(x) (MeNi, Co and FeNi) electrodes

Abstract Hydrogen evolution reaction (HER) was studied on amorphous CoP( x ), NiP( x ) and FeNiP( x ) electrodes, prepared by an electrolytic deposition. The activities of Ni and CoP( x ) electrodes prepared at room temperature are nearly equivalent, those of FeNiP( x ) are somewhat lower. Alloys prepared by the electrodeposition at room temperature are very active for the HER, while those prepared at elevated temperatures 80–90 °C are less active. It has been proved that the high activity of MeP( x ) electrodes is caused by dissolved hydrogen in the amorphous layer in the course of the electrodeposition.

Gel polymer electrolytes based on PMMA

New polymer gels (based on PMMA/PC) containing Li, Na, Mg, and Zn perchlorates were prepared. The conductivity of gels containing cations of smaller ionic radii (Li and Mg) is lower than that of the others.

Gel polymer electrolytes based on PMMA III. PMMA gels containing cadmium

Gel polymer electrolyte containing cadmium perchlorate was prepared by polymerisation of methylmethacrylate with a solution containing Cd perchlorate in propylene carbonate (PC). Electric conductivity, fundamental electrochemical properties and Cd electrodeposition were investigated. The deposition of Cd was fairly homogenous.