Abstract
MXenes are a recently discovered class of 2D materials with an excellent potential for energy storage applications. Because MXene surfaces are hydrophilic and attractive interaction forces between the layers are relatively weak, water molecules can spontaneously intercalate at ambient humidity and significantly influence the key properties of this 2D material. Using complementary X-ray and neutron scattering techniques, we demonstrate that intercalation with potassium cations significantly improves structural homogeneity and water stability in MXenes. In agreement with molecular dynamics simulations, intercalated potassium ions reduce the water self-diffusion coefficient by 2 orders of magnitude, suggesting greater stability of hydrated MXene against changing environmental conditions.
| Original language | English |
|---|---|
| Pages (from-to) | 8859-8863 |
| Number of pages | 5 |
| Journal | ACS Applied Materials and Interfaces |
| Volume | 8 |
| Issue number | 14 |
| DOIs | |
| State | Published - Apr 27 2016 |
Funding
This work was supported as part of the Fluid Interface Reactions, Structures and Transport (FIRST) Center, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences. Work at ORNL's Spallation Neutron Source is supported by the U.S. Department of Energy, Office of Basic Energy Sciences. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. Oak Ridge National Laboratory is managed by UT-Battelle, LLC, for U.S. DOE under Contract No. DEAC05-00OR22725. We are grateful to David J. Wesolowski for his support and critical reading of our manuscript.
Keywords
- MXenes
- ReaxFF simulation
- intercalation
- quasi-elastic neutron scattering
- water diffusion