Accuracy in Hydrogen Sorption Measurements

The accuracy of gas phase sorption measurements performed on potential hydrogen storage materials has been the subject of much controversy in recent years, particularly in the case of adsorption by carbon nanostructures. As the technological interest in the solid state storage of hydrogen increases, it has become increasingly necessary to investigate the methods used to determine the sorption properties, and hence the storage capacities, of new and existing materials. In this paper, we briefly review the different techniques available and recent literature on the topic, discuss the possible sources of errors and present some comparative measurements on some AB5 hydrogen-absorbing intermetallics. Equilibrium pressure-composition isotherm data measured on two LaNi5-xAlx samples using commercial gravimetric and volumetric instrumentation were found to be in good agreement with each other.JRC.F.2-Cleaner energie