Title: Capacitive deionization using carbon derived from an array of zeolitic-imidazolate frameworks

Abstract

Capacitive deionization (CDI) represents one of the most thermodynamically efficient technologies for brackish water desalination. Its performance is highly reliant on the surface properties of carbon-based electrodes. Zeolitic-imidazolate framework (ZIF)-derived carbon materials have emerged among the most promising candidates owing to their high structural and compositional tuneability. However, the impacts of the precursory ZIF structure on the properties of the final carbon, and therefore, CDI capacity and efficiency remain to be further explored. In this work, four Zn-based ZIFs with different side-chain substitutions on the imidazolates were synthesized on a gram scale with high yields to produce N-doped carbons by pyrolysis. Next, the resulting carbons along with four commercial carbon blacks were characterized physically and electrochemically to explore the structure-performance relationship. We demonstrated that the imidazole side-chain substitution alters the ZIF's decomposition during pyrolysis, influencing the elemental compositions, surface properties, wettability and graphitization levels. The diverse carbon properties result in variable double layer capacitance and charge-transfer resistance, ultimately impacting the CDI performance. Among these carbons, Zn (4abIm)2-C afforded the greatest salt adsorption capacity of 14.19 mg_NaCl$$·g_C^{–1}$$, while Zn (mIm)₂-C showed the highest overall salt adsorption capacity and rate; both exceeded the performance of the commercial carbon blacks.

Authors:

Wang, Hao  ^[1];

• Search DOE PAGES for author "Wang, Hao"
• Search DOE PAGES for ORCID "0000-0003-0674-0811"

Edaño, Louis ^[2]; Valentino, Lauren  ^[2];

• Search DOE PAGES for author "Valentino, Lauren"
• Search DOE PAGES for ORCID "0000-0002-6259-0304"

Lin, Yupo J.  ^[2];

• Search DOE PAGES for author "Lin, Yupo J."
• Search DOE PAGES for ORCID "0000-0003-2673-1453"

Palakkal, Varada Menon ^[2]; Hu, Dong-Li ^[3]; Chen, Biao-Hua ^[4]; Liu, Di-Jia  ^[5]

• Search DOE PAGES for author "Liu, Di-Jia"
• Search DOE PAGES for ORCID "0000-0003-1747-028X"

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+ Show Author Affiliations

1. Argonne National Lab. (ANL), Lemont, IL (United States); Beijing University of Technology (China)
2. Argonne National Lab. (ANL), Lemont, IL (United States)
3. Argonne National Lab. (ANL), Lemont, IL (United States). Center for Nanoscale Materials
4. Beijing University of Technology (China)
5. Argonne National Lab. (ANL), Lemont, IL (United States); Univ. of Chicago, IL (United States)

Publication Date:

Tue Aug 25 00:00:00 EDT 2020

Research Org.:

Argonne National Lab. (ANL), Argonne, IL (United States). Center for Nanoscale Materials

Sponsoring Org.:

USDOE Office of Science (SC); USDOE Laboratory Directed Research and Development (LDRD) Program

OSTI Identifier:

1777120

Alternate Identifier(s):

OSTI ID: 1658434

Grant/Contract Number:  

AC02-06CH11357

Resource Type:

Accepted Manuscript

Journal Name:

Nano Energy

Additional Journal Information:

Journal Volume: 77; Journal ID: ISSN 2211-2855

Publisher:

Elsevier

Country of Publication:

United States

Language:

English

Subject:

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; capacitive deionization; metal-organic frameworks, porous carbon, water desalination, structure-property relationship