Domain engineering of physical vapor deposited two-dimensional materials

摘要

Physical vapor deposited two-dimensional (2D) materials span larger areas compared to exfoliated flakes, but suffer from very small grain or domain sizes. In this letter, we fabricate freestanding molybdenum disulfide (MoS_2) and amorphous boron nitride (BN) specimens to expose both surfaces. We performed in situ heating in a transmission electron microscope to observe the domain restructuring in real time. The freestanding M0S2 specimens showed up to 100× increase in domain size, while the amorphous BN transformed in to polycrystalline hexagonal BN (h-BN) at temperatures around 600 ℃ much lower than the 850.1000 ℃ range cited in the literature.