Covalent surface modifications and superconductivity of two-dimensional metal carbide MXenes
Abstract
Unlike graphene and transition-metal dichalcogenides, two-dimensional transition-metal carbides (MXenes) have many surface sites that can be chemically modified. Etching of the aluminum layer of a parent MAX phase Ti 3 AlC 2 layered material with hydrofluoric acid leads to the MXene Ti 3 C 2 with various surface terminations. Molten salts can achieve uniform chloride terminations, but these are difficult to further modify. Kamysbayev et al. show that etching of MAX phases in molten cadmium bromide leads to bromide-terminated MXenes that can then be substituted with oxygen, sulfur, selenium, tellurium, and NH groups as well as with vacancy sites. The surface groups can alter electronic transport. For example, the Nb 2 C MXenes exhibit surface group–dependent superconductivity.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 21, 2020
- Source ID
- 10.1126/science.aba8311
Entities
People
- Alexander S Filatov
- Di Wang
- Dmitri V. Talapin
- Francisco Lagunas
- Huicheng Hu
- Robert F Klie
- Vladislav Kamysbayev
- Xue Rui
Organizations
- Air Force Office of Scientific Research
- Argonne National Laboratory
- National Science Foundation
- United States Department of Energy
- University of Chicago
- University of Illinois at Chicago