摘要
We report a large-scale, high-quality heterostructure composed of vertically-stacked graphene and two-dimensional(2D) germanium.The heterostructure is constructed by the intercalation-assisted technique.We first synthesize large-scale,single-crystalline graphene on Ir(111) surface and then intercalate germanium at the interface of graphene and Ir(111).The intercalated germanium forms a well-defined 2D layer with a 2 × 2 superstructure with respect to Ir(111).Theoretical calculations demonstrate that the 2D germanium has a double-layer structure.Raman characterizations show that the 2D germanium effectively weakens the interaction between graphene and Ir substrate, making graphene more like the intrinsic one.Further experiments of low-energy electron diffraction, scanning tunneling microscopy, and x-ray photoelectron spectroscopy(XPS) confirm the formation of large-scale and high-quality graphene/2D-germanium vertical heterostructure.The integration of graphene with a traditional 2D semiconductor provides a platform to explore new physical phenomena in the future.
We report a large-scale, high-quality heterostructure composed of vertically-stacked graphene and two-dimensional(2D) germanium.The heterostructure is constructed by the intercalation-assisted technique.We first synthesize large-scale,single-crystalline graphene on Ir(111) surface and then intercalate germanium at the interface of graphene and Ir(111).The intercalated germanium forms a well-defined 2D layer with a 2 × 2 superstructure with respect to Ir(111).Theoretical calculations demonstrate that the 2D germanium has a double-layer structure.Raman characterizations show that the 2D germanium effectively weakens the interaction between graphene and Ir substrate, making graphene more like the intrinsic one.Further experiments of low-energy electron diffraction, scanning tunneling microscopy, and x-ray photoelectron spectroscopy(XPS) confirm the formation of large-scale and high-quality graphene/2D-germanium vertical heterostructure.The integration of graphene with a traditional 2D semiconductor provides a platform to explore new physical phenomena in the future.
基金
Project supported by the National Key Research&Development Program of China(Grant Nos.2016YFA0202300 and 2018YFA0305800)
the National Natural Science Foundation of China(Grant Nos.61390501,61888102,and 51872284)
the Strategic Priority Research Program of Chinese Academy of Sciences(Grant Nos.XDB30000000 and XDB28000000)
Beijing Nova Program,China(Grant No.Z181100006218023)
the University of Chinese Academy of Sciences
