Abstract
The hindered rotations of molecular hydrogen adsorbed at low loadings into a number of partially ion-exchanged zeolites A, Y and X have been studied at low temperatures with the use of inelastic neutron scattering (INS) techniques. The factors that determine the sorption sites and strength of the interaction with the host material are found to be a complex combination of the type, charge and size of the cations, their coordination to the host framework, and accessibility to the hydrogen molecule as well as the relative acidity of the framework, and lead to important criteria for the development of more effective hybrid materials for hydrogen storage. The highest barriers to rotation were found for the undercoordinated, exposed Li+ cations in LiA and in LiX. Interaction with the extra framework Cu2+ and Zn2+ cations in zeolite A is found to be noticeably stronger than with the neutral Zn- or Cu- containing clusters in metal-organic framework compounds. Our observation that binding of hydrogen in these charged frameworks is strongly enhanced relative to those that are neutral suggests an important approach to improvement of porous materials as ambient temperature hydrogen storage media.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
