Facile Electrosynthesis of Ti3AlC2 and Its Derived Porous Carbon in Molten SaltFacile Electrosynthesis of Ti3AlC2 and Its Derived Porous CarbonJiang, Pang, S. Chen, Tian, Zhang, Wang, Xia, C. Chen, Li, Xu, Lu, and Zou

MAX phases and their derived materials (MXenes and CDCs) have received widespread attention because of their unique functional properties. However, the controllable synthesis of MAX phases and their derived powder materials remains challenging, and conventional preparation usually involves high-temperature sintering, mechanical crushing, and acid etching processes. Herein, this paper reports a facile electrochemical strategy for the synthesis of Ti3AlC2 powder and its derived carbon (Ti3AlC2-CDC) from TiO2/Al2O3/C precursors. In this strategy, the synthesis of Ti3AlC2 is achieved through molten salt electrolysis of a TiO2/Al2O3/C cathode directly, and the Ti3AlC2-CDC is then prepared through a subsequent molten salt electrochemical etching process. Systematical characterization and analysis of the synthesized Ti3AlC2 and Ti3AlC2-CDC were conducted, and the results indicate that the Ti3AlC2 synthesized by molten salt electrolysis is a micro-size powder, exhibiting a distinct lamellar structure with uniform element distribution. The synthesized Ti3AlC2-CDC powder exhibits a high specific surface area of 1268 m2 g−1 and excellent hierarchical porosity. As a conceptual demonstration, the energy storage properties of Ti3AlC2-CDC as electrode materials for lithium-ion battery (showing a specific capacity of 330 mAh g−1) and sodium-ion battery (showing a specific capacity of 100 mAh g−1) were preliminarily investigated, demonstrating excellent cycle stability in both cases. In summary, this work demonstrates the controllable synthesis of Ti3AlC2 and Ti3AlC2-CDC, offering advanced technological insights into the advancement of MAX phases and their derived powder materials.