Cryogenic mass spectroscopy for gas desorption from porous materials

Equipment, AAP 2018-4

Team: ICMPE, Chimie Métallurgique des Terres Rares

Project leaser: Claudia Zlotea


The CRYO TDS equipment will enable the study of thermal-desorption of adsorbed H2/D2 on porous materials at cryogenic temperatures starting from 25 K by accurate detection of gas species using mass spectroscopy. The aim is to characterize the active sites of adsorption, the site's binding energies, abundance, desorption kinetics and isotopic (H2/D2) behavior.

In the context of the "renewable energies" topic of the DIM RESPORE, H2 cryo-adsorption on porous hosts is an interesting approach to store large amount of hydrogen at cryogenic temperature, typically 77 K. Among multifarious porous materials, activated carbons and Metal-organic-frameworks (MOFs) have shown promising hydrogen capacities. Within this topic, our research activities are currently focusing on activated carbons and MOFs doped with noble metal clusters in order to increase the heat of H2 adsorption. To further understand the underling chemistry and to determine the interaction between H2 molecules and the porous hosts, the active sites of adsorption, the binding energies and the desorption kinetics have to be finely characterized. To provide such in-depth understanding of H2 adsorption on porous materials it is compulsory to combine cryogenic H2 adsorption at 25 K with the accuracy of gas detection provided by the mass spectrometer.

Moreover, such instrument can be also employed for the study of H2/D2 isotope separation and related quantum sieving on porous materials. The use of a mass spectrometer is compulsory to discriminate between H2 and D2 molecules.

To our knowledge, this is an unique instrument in Ile-de-France coupling gas cryo-adsorption and mass spectrometry.