| About this Abstract |
| Meeting |
MS&T23: Materials Science & Technology
|
| Symposium
|
Phase Transformations in Ceramics: Science and Applications
|
| Presentation Title |
Elevated Temperature Phase Control of Two-dimensional Mo2TiC2Tx Carbide Through Defect Engineering |
| Author(s) |
Brian Wyatt, Matthew Boebinger, Paul Kent, Zachary Hood, Shiba Adhikari, Srinivasa Kartik Nemani, Murali Muraleedharan, Annabelle Bedford, Wyatt Highland, Babak Anasori |
| On-Site Speaker (Planned) |
Brian Wyatt |
| Abstract Scope |
As a chemically diverse 2D transition metal carbide family, MXenes own many different atomic arrangements, such as ordered double transition metal (DTM) MXenes, where two transition metals occupy separate atomic layers interleaved by carbon. In this presentation, we demonstrate the phase behavior of an ordered DTM Mo2TiC2Tx MXene up to 2,000 °C in an inert environment and investigate the role of adsorbed alkali metal cations (Na+, K+) on controlling Mo2TiC2Tx¬’s phase behavior. We study this using in-situ two-dimensional x-ray diffraction (XRD2) and scanning transmission electron microscopy (STEM). The combination of in situ XRD2 and STEM methods with density functional theory, ex situ XRD2, x-ray photoelectron spectroscopy, and thermogravimetric analysis demonstrate the effect of alkali metal cations on controlling the phase stability and transformation of Mo2TiC2Tx MXenes. This presentation further establishes the tools for ceramic scientists to develop MXenes as a diverse and tunable family of nanoceramics for ultra-high temperature applications. |