A Facile Strategy for Controllable Synthesis of High-Quality Two-Dimensional Tellurium by Chemical Vapor Transport

Recently, as an elementary material, tellurium (Te) has received widespread attention for its high carrier mobility, intriguing topological properties and excellent environmental stability. However, it is difficult to obtain two-dimensional (2D) Te with high crystalline quality due to its intrinsic helical chain structure. Herein, a facile strategy for controllable synthesis of high quality 2D Te nanoflakes through chemical vapor transport (CVT) in one step is reported. With carefully tuning the growth kinetics determined mainly by temperature, tellurium nanoflakes in lateral size of up to ~40 μm with high crystallinity can be achieved. We also investigated the second harmonic generation (SHG) of Te nanoflakes, which demonstrates that it can be used as frequency doubling crystals and has potential applications in nonlinear optical devices. In addition, field effect transistor (FET) devices based on the as-grown 2D Te nanoflakes were fabricated and exhibited excellent electrical properties with high mobility of 379 cm2 V-1s-1.