Stacking of 2D Materials

Abstract

2D layered materials have sparked great interest from the perspective of basic physics and applied science in the past few years. Extraordinarily, many novel stacked structures that bring versatile properties and applications can be artificially assembled, as exemplified by vertical van der Waals (vdW) heterostructures, twisted multilayer 2D materials, hybrid dimensional structures, etc. Compared with the ordinary synthesis process, the stacking technique is a powerful strategy to achieve high‐quality and freely controlled 2D material stacked structures with atomic accuracy. This review highlights the most advanced stacking techniques involving the preparation, transfer, and stacking of high‐quality single crystal 2D materials. Apart from the 2D–2D stacked structures, 2D–0D, 2D–1D, and 2D–3D structures offer a prospective platform for the increasing application of 2D materials. The assembly strategy and physical properties of these stacked structures strongly depend on the factors in the stacking process, including the surface quality, angle control, and sample size. In addition, comparative analysis tables on the techniques involved are also available. The summary of these strategies and techniques will hopefully provide a valuable reference for relevant work.

Visualizing Van der Waals Epitaxial Growth of 2D Heterostructures

“…However, using this method, it is challenging to precisely control the size, shape, layer thickness, and interface properties of the heterostructures, along with being ill-suited for the scaleup needed for device applications. [12][13][14][15] Although considerable work has been done in the past few years for the direct synthesis of vdW heterostructures using physical vapor deposition and chemical vapor deposition (CVD), [16][17][18][19] the growth mechanisms are not well understood. [20][21][22] This is partly due to the fact that most studies on growth mechanisms relied on ex situ characterizations and often drew similarities to the growth of a single 2D vdW material (e.g., graphene or transition metal dichalcogenides (TMD)) on non-vdW substrates.…”

Two-Dimensional MoS2: Structural Properties, Synthesis Methods, and Regulation Strategies toward Oxygen Reduction

“…Currently, a variety of non-platinum metal-based ORR catalysts, such as defective carbon materials [4], heteroatom-doped metal-free carbon [5], transition metal/heteroatomco-doped carbon [6,7], intermetallic compounds [8], and metal nitrides [9], have been synthesized. Among them, two-dimensional (2D) materials with atomic or molecular thickness and infinite planar length exhibit peculiar physicochemical properties, including high specific surface area, adjustable band structure, and electromagnetic properties, which make 2D materials become one of the most important non-Pt-based ORR catalysts [10][11][12][13].…”

Thin-film electronics based on all-2D van der Waals heterostructures

“…However, this method suffers from some disadvantages, such as time-consuming, unrepeatable process, exfoliated flakes with irregular shape and size (e.g. lateral size usually less than 100 μm) [36]. To produce high-quality 2D thin flakes, the substrate, tape adhesiveness, and/or operational temperature should be optimized [31].…”

“…To form 2D vdW heterostructures for device applications, the pre-fabricated 2D flakes were transferred on the target substrate using polymer carriers [36]. In the following paragraphs, we mainly described the wet-transfer and dry-transfer processes.…”