Preparation of single-crystal metal substrates for the growth of high-quality two-dimensional materials

Abstract

Single-crystal metals are promising substrates for the epitaxial growth of two-dimensional (2D) materials owing to the absence of grain boundaries and distinctive symmetries. The rich arrangements of atoms on various crystal facets serve as an ideal platform for cutting-edge research on regulating the structures of the as-grown 2D materials. However, it is challenging to obtain large single-crystal metal materials, which hinders the in-depth exploration of single-crystal metal-2D material interface interactions. This review provides a critical summary of the recent progress towards achieving large-area single-crystal metals via anomalous grain growth and epitaxial deposition. Then, crucial roles of single-crystal metal substrates in the controlled growth of 2D materials are highlighted by discussing epitaxial growth of single crystals, rapid and low-temperature preparation, and wrinkle elimination. Finally, a perspective into future research on the preparation of single-crystal metals and 2D materials is provided, which is intended to inspire novel growth frontiers for 2D materials.