Electrochemical hydrogen evolution from solid tetraalkylammonium hydroxide hydrates

The electrochemical hydrogen evolution from tetraalkylammonium hydroxide hydrates (CH3)4NOH·5H2O, (CH3)4NOH·7.5H2O and (CH3)4NOH·10H2O has been studied in temperature range 110–340 K by linear sweep voltammetry and impedance spectroscopy. The results were analysed together with those previously obtained in other clathrate hydrates. lue of transfer coefficient of electrochemical hydrogen evolution reaction depends on temperature and this effect does not depend on electrolyte. It decreases from 0.4 at about 300 K down to about 0.1 at temperature larger than 100 K. The activation energy of electrochemical reaction is larger than that of protonic conductivity. It has been concluded that this reflects influence of electric field of the electrode on the reorientation of water molecules accompanying proton transfer.