Optoelectronic Materials: Ultrathin 2D GeSe2 Rhombic Flakes with High Anisotropy Realized by Van der Waals Epitaxy (Adv. Funct. Mater. 47/2017)

A new member (GeSe2) of the 2D material family is described by Tianyou Zhai and co-workers in article number 1703858. For the first time, ultrathin single-crystalline β-GeSe2 rhombuses (≈7 nm) are realized by van der Waals epitaxy with halide-assistance. A photo-detector based on a GeSe2 rhombus shows a high responsivity of 2.5 A W−1 and fast response of ≈0.2 s.