Super Metalated Frameworks as Hydrogen Sponges

Technical Report · Thu Nov 29 00:00:00 EST 2018

DOI:https://doi.org/10.2172/1489821· OSTI ID:1489821

Yaghi, Omar ^[1]

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1. Univ. of California, Berkeley, CA (United States); University of California, Berkeley

The most promising strategy towards the development of practical on-board hydrogen fuel cells for light-duty-vehicles is the application of materials that store hydrogen via physisorption. Such materials require high hydrogen storage capacities and stabilities. Metal-Organic Frameworks (MOFs) are crystalline porous materials comprised of metal clusters linked by organic struts where each component can be systematically altered or functionalized. This tunability coupled with their highly porous nature make MOFs ideal candidates for gas storage applications. The state-of-the-art MOF based absorbent (MOF-74 analogue) utilizes coordinatively unsaturated metal sites (open metal sites) which exhibit strong interactions with H₂ (Qst = 13 KJ/mol) producing the record figure of merit (12 g/L and 0.9 wt% at 25 ºC 100 bar) [3]. However, these values remain below the DOE 2025 target for hydrogen storage. To increase the interaction strength between the framework and H₂, we have prepared a highly porous, functionalizable MOF (Mg-IRMOF-74-III). The organic linker of this MOF was functionalized with primary amines that were used to install metal-binding ligands for subsequent metalation. The newly installed open metal sites have slightly improved H₂ storage capacity at 77 K via weak interactions. However, the primary amines of the organic linkers have lead to a dramatic decrease in the H₂ capacity due to the interaction of the amines with the open metal-sites of the inorganic nodes. The conclusions of the present project pave the way for design of supermetalated crystalline materials for hydrogen storage to meet the DOE 2025 target in the future

• Research Organization: Univ. of California, Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Fuel Cell Technologies Office (EE-3F)
• DOE Contract Number: EE0008094
• OSTI ID: 1489821
• Report Number(s): DOE-UCB--08094
• Country of Publication: United States
• Language: English

Related Subjects

08 HYDROGEN
25 ENERGY STORAGE
36 MATERIALS SCIENCE
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
77 NANOSCIENCE AND NANOTECHNOLOGY
Metal organic frameworks
analytical chemistry
hydrogen storage
inorganic chemistry
postsynthetic modification
x-ray diffraction