Cobalt and molybdenum activated electrodes in foam based alkaline electrolysis cells at 150–250 °C and 40 bar

•A new type of alkaline electrolysis cell has been developed.•Co- and Mo-oxide electro-catalysts on nickel foam based gas diffusion electrodes were used.•Potassium hydroxide as electrolyte was immobilized in a porous SrTiO3 structure.•The performance of the cells have been analyzed at 150–250 °C at 40 bar.•Current densities of 1.1 A cm−2 and 2.3 A cm−2 have been measured at 1.5 V and 1.75 V.

A new type of alkaline electrolysis cells with nickel foam based gas diffusion electrodes and KOH (aq) immobilized in mesoporous SrTiO3 has been developed and tested at temperatures of 150 °C, 200 °C and 250 °C at a pressure of 40 bar. Two cells have been characterized during the 270 h long test, using impedance spectroscopy, cyclic voltammetry and chronoamperometry at an applied cell voltage of 1.5 V, 1.625 V and 1.75 V. The performance of the electrolysis cells was improved by the addition of cobalt oxide and molybdenum oxide as nano sized electro-catalysts. At 250 °C current densities of 1.1 A cm−2 and 2.3 A cm−2 were obtained at cell voltages of 1.5 V and 1.75 V, respectively.