From 2D MXenes to 3D Carbides: Transformation of Ti 3 C 2 T z Thin Films into TiC x Carbide Nanolayers

High Resolution Image Download MS PowerPoint Slide MXenes are renowned for their versatile uses in various scientific fields as 2D materials, but they also show potential in structural applications utilizing their high-temperature transformation into transition-metal carbides with unique morphologies. Herein, we developed a method to study this transformation in model systems. As a proof-of-concept, MXene thin films (≤20 nm thickness) were deposited on sapphire and subjected to high temperature (1400 °C) and moderate pressure (18 MPa), transforming them into nanolamellar carbides. Structural and compositional analyses of the interface revealed that the Ti 3 C 2 T z transformed into TiC x O y (with ∼13 at% O), while halide surface terminations were removed. A small fraction of Li (∼0.2 at%) was detected within the transformed nanolayer, stabilized by the presence of O in the oxycarbide lattice. Ultimately, this methodology provides a framework for studying the MXene-to-MX transformation under controlled conditions, enabling the rational design of nanocomposites and bonding nanolayers for advanced structural and functional materials.