Hydrogen absorption by a palladium electrode from a protic ionic liquid at temperatures exceeding 100 °C

Abstract Hydrogen adsorption in a palladium electrode driven by the electrochemical reduction of protons from a protic ionic liquid is presented. The amounts of hydrogen absorbed and desorbed in thin Pd films is similar in both the diethylmethylammonium-trifluoromethanesulfonate ionic liquid and in an aqueous H 2 SO 4 solution, reaching H/Pd atomic ratios of 0.7 to 0.8. The electrochemical quartz crystal microbalance technique showed decreased absorption and desorption rates due to the slower proton transfer between the protic ionic liquid and the electrode. The use of this thermally stable ionic liquid allowed absorbing and desorbing hydrogen at temperatures up to 125 °C, increasing the rate of the reactions.