Title: Enhanced Thermal Conductivity in a Diamine-Appended Metal-Organic Framework as a Result of Cooperative CO₂ Adsorption

Abstract

Using diamine-appended variants of the metal-organic framework M₂(dobpdc) (M = Mg, Mn, Fe, Co, Zn; dobpdc^4- = 4,4'-dioxidobiphenyl-3,3'-dicarboxylate) exhibit exceptional CO₂ capture properties owing to a unique cooperative adsorption mechanism, and thus hold promise for use in the development of energy- and cost-efficient CO₂ separations. Understanding the nature of thermal transport in these materials is essential for such practical applications, however, as temperature rises resulting from exothermic CO₂ uptake could potentially offset the energy savings offered by such cooperative adsorbents. Here, molecular dynamics (MD) simulations are employed in investigating thermal transport in bare and e-2-appended Zn₂(dobpdc) (e-2 = N-ethylethylenediamine), both with and without CO₂ as a guest. In the absence of CO₂, the appended diamines function to enhance thermal conductivity in the ab-plane of e-2-Zn₂(dobpdc) relative to the bare framework, as a result of noncovalent interactions between adjacent diamines that provide additional heat transfer pathways across the pore channel. Upon introduction of CO₂, the thermal conductivity along the pore channel (the c-axis) increases due to the cooperative formation of metal-bound ammonium carbamates, which serve to create additional heat transfer pathways. In contrast, the thermal conductivity of the bare framework remains unchanged in the presence of zinc-bound CO₂ but decreases inmore » the presence of additional adsorbed CO₂.« less

Authors:

Babaei, Hasan  ^[1];

• Search DOE PAGES for author "Babaei, Hasan"
• Search DOE PAGES for ORCID "0000-0002-3291-0290"

Lee, Jung-Hoon  ^[2];

• Search DOE PAGES for author "Lee, Jung-Hoon"
• Search DOE PAGES for ORCID "0000-0002-2983-678X"

Dods, Matthew N. ^[1]; Wilmer, Christopher E.  ^[3];

• Search DOE PAGES for author "Wilmer, Christopher E."
• Search DOE PAGES for ORCID "0000-0002-7440-5727"

Long, Jeffrey R.  ^[4]

• Search DOE PAGES for author "Long, Jeffrey R."
• Search DOE PAGES for ORCID "0000-0002-5324-1321"

---

+ Show Author Affiliations

1. Univ. of California, Berkeley, CA (United States)
2. Korean Institute of Science and Technology (KIST), Seoul (Korea, Republic of)
3. Univ. of Pittsburgh, PA (United States)
4. Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

Publication Date:

Tue Sep 01 00:00:00 EDT 2020

Research Org.:

Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES); National Science Foundation (NSF)

OSTI Identifier:

1842993

Grant/Contract Number:  

AC02-05CH11231; CBET-1804011; OAC-1931436; SC0019992

Resource Type:

Accepted Manuscript

Journal Name:

ACS Applied Materials and Interfaces

Additional Journal Information:

Journal Volume: 12; Journal Issue: 40; Journal ID: ISSN 1944-8244

Publisher:

American Chemical Society (ACS)

Country of Publication:

United States

Language:

English

Subject:

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; metal-organic framework; diamine-M2(dobpdc); heat transfer; CO2; phonon scattering