RUI: Probing adsorbate interactions in metal-organic frameworks using site selective spectroscopy

Oberlin College, Oberlin OH

Investigators

Abstract

In this project funded by the Chemical Structure, Dynamics and Mechanisms-A program of the Chemistry Division, Professor Stephen FitzGerald of Oberlin College investigates novel porous materials for both storing and separating the different isotopes of hydrogen gas. The lack of viable, on-board hydrogen storage is seen as the major impediment to the development of fuel cell powered automobiles. In the case of hydrogen isotopes, used extensively by the nuclear, medical, and scientific research communities, it is the difficulty of isotope separation that dramatically increases cost and inhibits greater use. To meet these challenges this project focuses on using a combination of infrared and mass spectroscopy to understand the quantum behavior of adsorbate molecules confined within the pores of metal-organic frameworks. Temperature and concentration dependent spectra revealing site-specific enthalpy and entropy of adsorption differentiate between different binding mechanisms and establish the viability of isotopic separation using quantum sieving effects arising from differences in zero-point energy. This information is used to guide collaborators at national laboratories and research universities in the fabrication of new materials with optimized properties for gas storage and separation. Beyond the societal benefits of hydrogen powered cars and more efficient gas separation techniques, this work has a broader impact through mentoring of the undergraduate students working one on one with the principal investigator. These students perform all the research at Oberlin College, while gaining experience of a larger collaboration of research universities and national laboratories.