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Title: Molecular Retrofitting Adapts a Metal–Organic Framework to Extreme Pressure

Abstract

Despite numerous studies on chemical and thermal stability of metal-organic frameworks (MOFs), mechanical stability remains largely undeveloped. No strategy exists to control the mechanical deformation of MOFs under ultrahigh pressure, to date. We show that the mechanically unstable MOF-520 can be retrofitted by precise placement of a rigid 4,4'-biphenyldicarboxylate (BPDC) linker as a "girder" to afford a mechanically robust framework: MOF-520-BPDC. This retrofitting alters how the structure deforms under ultrahigh pressure and thus leads to a drastic enhancement of its mechanical robustness. While in the parent MOF-520 the pressure transmitting medium molecules diffuse into the pore and expand the structure from the inside upon compression, the girder in the new retrofitted MOF-520-BPDC prevents the framework from expansion by linking two adjacent secondary building units together. As a result, the modified MOF is stable under hydrostatic compression in a diamond-anvil cell up to 5.5 gigapascal. The increased mechanical stability of MOF-520-BPDC prohibits the typical amorphization observed for MOFs in this pressure range. Direct correlation between the orientation of these girders within the framework and its linear strain was estimated, providing new insights for the design of MOFs with optimized mechanical properties.

Authors:
ORCiD logo [1];  [1];  [2]; ORCiD logo [3]
  1. Univ. of California, Berkeley, CA (United States). Dept. of Chemistry; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Kavli Energy NanoSciences Inst., Berkeley, CA (United States); Berkeley Global Science Inst., Berkeley, CA (United States)
  2. King Abdulaziz City for Science and Technology, Riyadh (Saudi Arabia)
  3. Univ. of California, Berkeley, CA (United States). Dept. of Chemistry; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Kavli Energy NanoSciences Inst., Berkeley, CA (United States); Berkeley Global Science Inst., Berkeley, CA (United States); King Abdulaziz City for Science and Technology, Riyadh (Saudi Arabia)
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); National Science Foundation (NSF)
OSTI Identifier:
1411661
Grant/Contract Number:
AC02-05CH11231; SC0001015; EAR 11-57758
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
ACS Central Science
Additional Journal Information:
Journal Volume: 3; Journal Issue: 6; Journal ID: ISSN 2374-7943
Publisher:
American Chemical Society (ACS)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Kapustin, Eugene A., Lee, Seungkyu, Alshammari, Ahmad S., and Yaghi, Omar M. Molecular Retrofitting Adapts a Metal–Organic Framework to Extreme Pressure. United States: N. p., 2017. Web. doi:10.1021/acscentsci.7b00169.
Kapustin, Eugene A., Lee, Seungkyu, Alshammari, Ahmad S., & Yaghi, Omar M. Molecular Retrofitting Adapts a Metal–Organic Framework to Extreme Pressure. United States. doi:10.1021/acscentsci.7b00169.
Kapustin, Eugene A., Lee, Seungkyu, Alshammari, Ahmad S., and Yaghi, Omar M. Wed . "Molecular Retrofitting Adapts a Metal–Organic Framework to Extreme Pressure". United States. doi:10.1021/acscentsci.7b00169. https://www.osti.gov/servlets/purl/1411661.
@article{osti_1411661,
title = {Molecular Retrofitting Adapts a Metal–Organic Framework to Extreme Pressure},
author = {Kapustin, Eugene A. and Lee, Seungkyu and Alshammari, Ahmad S. and Yaghi, Omar M.},
abstractNote = {Despite numerous studies on chemical and thermal stability of metal-organic frameworks (MOFs), mechanical stability remains largely undeveloped. No strategy exists to control the mechanical deformation of MOFs under ultrahigh pressure, to date. We show that the mechanically unstable MOF-520 can be retrofitted by precise placement of a rigid 4,4'-biphenyldicarboxylate (BPDC) linker as a "girder" to afford a mechanically robust framework: MOF-520-BPDC. This retrofitting alters how the structure deforms under ultrahigh pressure and thus leads to a drastic enhancement of its mechanical robustness. While in the parent MOF-520 the pressure transmitting medium molecules diffuse into the pore and expand the structure from the inside upon compression, the girder in the new retrofitted MOF-520-BPDC prevents the framework from expansion by linking two adjacent secondary building units together. As a result, the modified MOF is stable under hydrostatic compression in a diamond-anvil cell up to 5.5 gigapascal. The increased mechanical stability of MOF-520-BPDC prohibits the typical amorphization observed for MOFs in this pressure range. Direct correlation between the orientation of these girders within the framework and its linear strain was estimated, providing new insights for the design of MOFs with optimized mechanical properties.},
doi = {10.1021/acscentsci.7b00169},
journal = {ACS Central Science},
number = 6,
volume = 3,
place = {United States},
year = {Wed Jun 07 00:00:00 EDT 2017},
month = {Wed Jun 07 00:00:00 EDT 2017}
}

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