A Red‐Phosphorous‐Assisted Ball‐Milling Synthesis of Few‐Layered Ti₃C₂T_x (MXene) Nanodot Composite

Abstract Layered two‐dimensional (2D) early transition metal carbides (MXenes) are a new class of 2D materials with established activity for electrochemical energy conversion and storage. The use of MXenes is expected to increase by reducing their lateral size to the nanoscale. Herein, using Ti₃C₂T_x (T=O, OH, F) MXenes as an example, we show that μm‐sized MXenes can be reduced in size to ≈6 nm nanodots by ball‐milling with red phosphorous (P). It is remarkable almost all starting MXenes were converted to nanodots with this method. The Ti₃C₂T_x surface O groups interacted with P strongly and chemically to drive the nanodots formation. Ti₃C₂T_x nanodots (TNDs) with different sizes could also be obtained by ball‐milling Ti₃C₂T_x with other solid‐state elements such as carbon, sulfur and silicon. The as‐prepared TNDs and P composite was evaluated as a sodium‐ion battery anode material. A good sodiation capacity (≈600 mA h g⁻¹) at 260 mA g⁻¹ and good cycle stability for 150 cycles were shown.