Title: Direct Assessment of Nanoconfined Water in 2D Ti₃C₂ Electrode Interspaces by a Surface Acoustic Technique

Abstract

Although significant progress has been achieved in understanding of ion-exchange mechanisms in the new family of 2D transition metal carbides and nitrides known as MXenes, direct gravimetric assessment of water insertion into the MXene interlayer spaces and mesopores has not been reported so far. Concurrently, the latest research on MXene and Birnessite electrodes shows that nanoconfined water dramatically improves their gravimetric capacity and rate capability. Hence, quantification of the amount of confined water in solvated electrodes is becoming an important goal of energy-related research. Using the recently developed and highly sensitive method of in situ hydrodynamic spectroscopy (based on surface-acoustic probing of solvated interfaces), we provide clear evidence that typical cosmotropic cations (Li⁺, Mg²⁺, and Al³⁺) are inserted into the MXene interspaces in their partially hydrated form, in contrast to the insertion of chaotropic cations (Cs⁺ and TEA⁺), which effectively dehydrate the MXene. These new findings provide important information about the charge-storage mechanisms in layered materials by direct quantification and efficient control (management) over the amount of confined fluid in a variety of solvated battery/supercapacitor electrodes. Here, we believe that the proposed monitoring of water content as a function of the nature of ions can be equally applied to solvatedmore » biointerfaces, such as the ion channels of membrane proteins.« less

Authors:

Shpigel, Netanel ^[1]; Levi, Mikhael D.  ^[1];

• Search DOE PAGES for author "Levi, Mikhael D."
• Search DOE PAGES for ORCID "0000-0002-4984-6678"

Sigalov, Sergey ^[1]; Mathis, Tyler S. ^[2]; Gogotsi, Yury ^[2]; Aurbach, Doron  ^[1]

• Search DOE PAGES for author "Aurbach, Doron"
• Search DOE PAGES for ORCID "0000-0001-8047-9020"

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+ Show Author Affiliations

1. Bar-Ilan Univ., Ramat-Gan (Israel)
2. Drexel Univ., Philadelphia, PA (United States)

Publication Date:

Thu Jun 21 00:00:00 EDT 2018

Research Org.:

Energy Frontier Research Centers (EFRC) (United States). Fluid Interface Reactions, Structures and Transport Center (FIRST); UT-Battelle LLC/ORNL, Oak Ridge, TN (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES); Binational Science Foundation (BSF); Israel Ministry of Science Technology and Space

OSTI Identifier:

1566364

Grant/Contract Number:  

AC05-00OR22725; 2014083/2016; 66032

Resource Type:

Accepted Manuscript

Journal Name:

Journal of the American Chemical Society

Additional Journal Information:

Journal Volume: 140; Journal Issue: 28; Journal ID: ISSN 0002-7863

Publisher:

American Chemical Society (ACS)

Country of Publication:

United States

Language:

English

Subject:

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; catalysis (heterogeneous); solar (fuels); energy storage (including batteries and capacitors); hydrogen and fuel cells; electrodes - solar; mechanical behavior; charge transport; materials and chemistry by design; synthesis (novel materials); hydrodynamics; cations; molecules; electrodes ions