About this Abstract |
| Meeting |
MS&T26: Materials Science & Technology
|
| Symposium
|
Controlled Synthesis, Processing, and Applications of Structural and Functional Nanomaterials
|
| Presentation Title |
Unraveling MAX Phase Etching: Chemical Interactions, Lattice Response, and Front Propagation |
| Author(s) |
Milos Dujovic, Vrushali Kothastane , Sisi Xiang, Vikram Deshpande, Jodie Lutkenhaus, Micah Green, Ankit Srivastava, Miladin Radovic |
| On-Site Speaker (Planned) |
Milos Dujovic |
| Abstract Scope |
MXenes are a rapidly expanding class of two-dimensional transition metal carbides, nitrides, and carbonitrides derived from MAX phases through selective etching of A-group elements, exhibiting exceptional conductivity, chemical tunability, and structural stability across diverse applications. Despite over 340 identified MAX phases, only ~50 MXenes have been experimentally synthesized, highlighting a limited understanding of their transformation mechanisms. This study investigates the etching behavior of Ti3AlC2 using fabricated microwalls with controlled crystallographic orientations, where long edges are aligned parallel to basal planes and exposed to hydrofluoric acid. By tracking the interface between etched and unetched regions, we provide the first direct experimental evidence of localized lattice expansion in partially delaminated MXene domains and in the adjacent MAX phase near the etching front. MAX phase expansion suggests lattice pre-conditioning as potential rate-limiting step in the MAX-to-MXene transformation, while MXene expansion reflects accordion structure formation, together establishing a coupled chemical-structural mechanism governing etching. |