Nature of Terminating Hydroxyl Groups and Intercalating Water in Ti3C2Tx MXenes: A Study by 1H Solid-State NMR and DFT Calculations
Date
Authors
Major Professor
Advisor
Committee Member
Journal Title
Journal ISSN
Volume Title
Publisher
Authors
Research Projects
Organizational Units
Ames National Laboratory is a government-owned, contractor-operated national laboratory of the U.S. Department of Energy (DOE), operated by and located on the campus of Iowa State University in Ames, Iowa.
For more than 70 years, the Ames National Laboratory has successfully partnered with Iowa State University, and is unique among the 17 DOE laboratories in that it is physically located on the campus of a major research university. Many of the scientists and administrators at the Laboratory also hold faculty positions at the University and the Laboratory has access to both undergraduate and graduate student talent.
The Department of Chemistry seeks to provide students with a foundation in the fundamentals and application of chemical theories and processes of the lab. Thus prepared they me pursue careers as teachers, industry supervisors, or research chemists in a variety of domains (governmental, academic, etc).
History
The Department of Chemistry was founded in 1880.
Dates of Existence
1880-present
Related Units
- College of Liberal Arts and Sciences (parent college)
Journal Issue
Is Version Of
Versions
Series
Department
Abstract
Since the discovery of two-dimensional transition metal carbides, referred to as MXenes, research efforts have targeted their applications in energy storage, as lithium-ion batteries and supercapacitors. This interest is attributable to MXenes’ large volumetric capacitance, high rate handling capability, and stable cycling performance, which largely rely on the surface chemistry provided by the terminating groups, such as −OH, −O, and −F. However, the atomic-scale characterization of these surface terminations is challenging for diffraction methods. Solid-state (SS)NMR spectroscopy, especially 1H SSNMR, is a promising approach for scrutinizing the surface terminations and the intercalated water on an atomistic-scale; yet, only a few SSNMR studies of MXenes have been reported to date, offering conflicting results and limited understanding of −OH terminations. Here, we used 1H SSNMR experiments in concert with the DFT calculations of NMR parameters to identify multiple types of −OH groups residing on the external and internal surfaces in a commonly studied MXene, Ti3C2Tx. The study also identifies bulklike water trapped between the MXene flakes and interfacial water stranded on the surface. Lastly, two-dimensional 1H–1H correlation spectra elucidated the water–surface interactions and the mechanism of water deintercalation upon annealing.