Title: Influence of Metal Identity on Light-Induced Switchable Adsorption in Azobenzene-Based Metal–Organic Frameworks

Abstract

Energy-efficient capture and release of small gas molecules, particularly carbon dioxide (CO₂) and methane (CH₄), are of significant interest in academia and industry. Porous materials such as metal–organic frameworks (MOFs) have been extensively studied, as their ultrahigh porosities and tunability enable significant amounts of gas to be adsorbed while also allowing specific applications to be targeted. However, because of the microporous nature of MOFs, the gas adsorption performance is dominated by high uptake capacity at low pressures, limiting their application. Hence, methods involving stimuli-responsive materials, particularly light-induced switchable adsorption (LISA), offer a unique alternative to thermal methods. Here, we report the mechanism of a well-known LISA system, the azobenzene-based material PCN-250, for CO₂ and CH₄ adsorption. There is a noticeable difference in the LISA effect dependent on the metal cluster involved, with the most significant being PCN-250-Al, where the adsorption can change by 83.1% CH₄ and 56.1% CO₂ at 298 K and 1 bar and inducing volumetric storage changes of 36.2 and 33.9 cm³/cm³ at 298 K between 5 and 85 bar (CH₄) and 2 and 9 bar (CO₂), respectively. Using UV light in both single-crystal X-ray diffraction and gas adsorption testing, we show that upon photoirradiation, the framework undergoesmore » a “localized heating” phenomenon comparable to an increase of 130 K for PCN-250-Fe and improves the working capacity. Furthermore, this process functions because of the constrained nature of the ligand, preventing the typical trans-to-cis isomerization observed in free azobenzene. In addition, we observed that the degree of localized heating is highly dependent on the metal cluster involved, with the series of isostructural PCN-250 systems showing variable performance based upon the degree of interaction between the ligand and the metal center.« less

Authors:

Drake, Hannah F. ^[1]; Xiao, Zhifeng ^[2]; Day, Gregory S. ^[1]; Vali, Shaik Waseem ^[2]; Daemen, Luke L. ^[3]; Cheng, Yongqiang  ^[3];

• Search DOE PAGES for author "Cheng, Yongqiang"
• Search DOE PAGES for ORCID "0000-0002-3263-4812"

Cai, Peiyu ^[2]; Kuszynski, Jason E. ^[2]; Lin, Hengyu ^[2]; Zhou, Hong-Cai  ^[2];

• Search DOE PAGES for author "Zhou, Hong-Cai"
• Search DOE PAGES for ORCID "0000-0002-9029-3788"

Ryder, Matthew R.  ^[3]

• Search DOE PAGES for author "Ryder, Matthew R."
• Search DOE PAGES for ORCID "0000-0002-1363-8148"

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+ Show Author Affiliations

1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Texas A & M Univ., College Station, TX (United States)
2. Texas A & M Univ., College Station, TX (United States)
3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Publication Date:

Tue Feb 22 00:00:00 EST 2022

Research Org.:

Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES); USDOE Office of Fossil Energy (FE); Qatar National Research Fund; National Energy Research Scientific Computing Center (NERSC); National Institute of Health

OSTI Identifier:

1883949

Grant/Contract Number:  

AC05-00OR22725; SC0014664; AC02-05CH11231; SC0001015; NPRP9-377-1-080; R35 GM127021

Resource Type:

Accepted Manuscript

Journal Name:

ACS Applied Materials and Interfaces

Additional Journal Information:

Journal Volume: 14; Journal Issue: 9; 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 frameworks; gas storage; photoresponsive materials; light-induced switchable adsorption; coordination chemistry; energy storage; adsorption; azobenzene; ligands; materials; metals