Controllable Growth of 2D Magnetic Fe3GeTe2 Nanosheets via Subtractive-Element Strategy

Abstract

Fe3GeTe2, a two-dimensional (2D) van der Waals magnet with intrinsic long-range ferromagnetic ordering, has attracted great attention in recent years. However, the synthesis of large-area Fe3GeTe2 crystals by chemical vapor deposition (CVD) remains challenging, for it is difficult to control the reactions among three precursors. Herein, we demonstrate the growth of large-area van der Waals Fe3GeTe2 nanosheets via the subtractive element growth mechanism. Different from previous methods including three precursors, we selected GeTe and FeCl3 as precursors. The obtained nanosheets exhibit triangular or hexagonal shapes, with lateral sizes up to 162 μm and thicknesses down to 5.6 nm. XRD, Raman, HRTEM, and SAED were used to characterize the crystal structure and phase purity, while EDS, and XPS analyses further verified the chemical composition and valence states. Magnetic measurements reveal robust ferromagnetism with a Curie temperature of ∼230 K. This work establishes a feasible chemical strategy for the scalable preparation of 2D Fe3GeTe2, thereby advancing its prospects in spintronic applications.