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Two‐Dimensional Metal Chalcogenide Heterostructures: Designed Growth and Emerging Novel Applications

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Advanced Materials Interfaces
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Dongyan Li
Dongyan Li
Dongyan Li
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Zexin Li
Zexin Li
Zexin Li
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Ping Chen at Hefei University of Technology
Ping Chen
Lejing Pi
Lejing Pi
Lejing Pi
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Abstract and Figures

There has been a renewed interest in 2D metal chalcogenide heterostructures (2DMCHs) in the context of their exceptional optoelectronic properties and potential for a wide variety of practical applications. However, the controllable synthesis of 2DMCHs remains a huge challenge. Recently, chemical vapor deposition (CVD) has been proposed to be an efficient way to realize high‐quality, large‐scale, and layer‐controllable 2D materials and has also shown high feasibility in 2DMCHs. Here, the latest controllable CVD growth strategies of 2DMCHs are introduced. The designed growth techniques mainly focus on three vital factors in CVD: source supply, mass transport, and substrate engineering. Then, the emerging novel applications of 2DMCHs are also systematically reviewed with particular attention to memory, infrared photodetector, and moiré superlattice, which have demonstrated significant progress in recent years. Finally, future opportunities and remaining challenges concerning the developments of 2DMCHs are presented. 2D metal chalcogenide heterostructures (2DMCHs) are a current research hotspot due to their unique properties. The review highlights research advances in controllable chemical vapor deposition growth of 2DMCHs, focusing on additives‐assisted process, substrate engineering, and mass transfer process. The novel applications and physical phenomenon of 2DMCHs in memory, infrared photodetector, and moiré superlattice are also considered.
Schematic summarizing of the research contents (growth and applications of 2DMCHs).
Schematic summarizing of the research contents (growth and applications of 2DMCHs).
… 
Schematic representation of the fundamental steps in a CVD procedure.
Schematic representation of the fundamental steps in a CVD procedure.
… 
Diagram of additives‐assisted growth (Te/salt). a) Schematic diagram illustrating the forming of intermediate products via the added additives. b) Schematic of the lateral heterostructure. c) Optical image of the NbS2/MoS2 vertical heterojunction via the added NaCl. d) The simulated STEM image of the NbS2/MoS2 heterojunction based on an R‐type stacking model. e) Atomic model of the NbS2/MoS2 heterojunction from top and side view with an R‐type stacking orientation. c–e) Reproduced with permission.[¹³¹] Copyright 2018, American Chemical Society. f) The atomic model of the lateral heterostructure. g) Optical image of the WS2/MoS2 in‐plane heterostructure via the added Te. h,i) Atomic resolution Z‐contrast images and the corresponding atomic models of the atomically sharp lateral interfaces along the zigzag and armchair directions. g–i) Reproduced with permission.[¹⁰³] Copyright 2014, Nature Publishing Group. Scale bars: 2 nm (d); 0.5 nm (h).
Diagram of additives‐assisted growth (Te/salt). a) Schematic diagram illustrating the forming of intermediate products via the added additives. b) Schematic of the lateral heterostructure. c) Optical image of the NbS2/MoS2 vertical heterojunction via the added NaCl. d) The simulated STEM image of the NbS2/MoS2 heterojunction based on an R‐type stacking model. e) Atomic model of the NbS2/MoS2 heterojunction from top and side view with an R‐type stacking orientation. c–e) Reproduced with permission.[¹³¹] Copyright 2018, American Chemical Society. f) The atomic model of the lateral heterostructure. g) Optical image of the WS2/MoS2 in‐plane heterostructure via the added Te. h,i) Atomic resolution Z‐contrast images and the corresponding atomic models of the atomically sharp lateral interfaces along the zigzag and armchair directions. g–i) Reproduced with permission.[¹⁰³] Copyright 2014, Nature Publishing Group. Scale bars: 2 nm (d); 0.5 nm (h).
… 
a) Schematic diagram illustrating the growth of MoS2/h‐BN heterostructures via the Ni–Ga alloy as the substrate. Reproduced with permission.[¹³⁵] Copyright 2016, American Chemical Society. b) Schematic for the growth of the 100% overlapped ReS2/WS2 heterostructure. c) Theoretical simulations explaining the twinned growth of ReS2/WS2 on Au substrate. d,e) Optical image of ReS2/WS2 and the corresponding Raman mappings of the E2g mode of ReS2 and WS2. f) Fast Fourier transform (FFT) of the vertical heterostructures showing a rotation angle of 5.6°. g) Tentative orientation model for the 100% overlapped ReS2/WS2 heterostructure with a rotation angle to be about 5.6°. b–g) Reproduced under the terms of the CC‐BY 4.0 license.[¹⁶⁰] Copyright 2016, The Authors, published by Springer Nature. Scale bars: 5 µm (d,e); 4 nm⁻¹ (f).
a) Schematic diagram illustrating the growth of MoS2/h‐BN heterostructures via the Ni–Ga alloy as the substrate. Reproduced with permission.[¹³⁵] Copyright 2016, American Chemical Society. b) Schematic for the growth of the 100% overlapped ReS2/WS2 heterostructure. c) Theoretical simulations explaining the twinned growth of ReS2/WS2 on Au substrate. d,e) Optical image of ReS2/WS2 and the corresponding Raman mappings of the E2g mode of ReS2 and WS2. f) Fast Fourier transform (FFT) of the vertical heterostructures showing a rotation angle of 5.6°. g) Tentative orientation model for the 100% overlapped ReS2/WS2 heterostructure with a rotation angle to be about 5.6°. b–g) Reproduced under the terms of the CC‐BY 4.0 license.[¹⁶⁰] Copyright 2016, The Authors, published by Springer Nature. Scale bars: 5 µm (d,e); 4 nm⁻¹ (f).
… 
a) Schematic diagram of solution‐processed precursor deposition and the growth procedure of MoS2–WS2 in‐plane heterostructures. b–d) OM image of a scalable MoS2–WS2 heterostructure and the corresponding Raman mapping of the E′ mode of MoS2 and the A′1 mode of WS2. a–d) Reproduced with permission.[¹³²] Copyright 2019, American Chemical Society. e) Schematic illustration showing the synthesis of MoS2–WS2 lateral heterostructures. f) Optical micrograph of an as‐grown heterostructure. g,h) PL results from different regions and Raman mapping in (f). e–h) Reproduced with permission.[¹⁷⁶] Copyright 2018, Elsevier. Scale bars: 50 µm (b–d).
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a) Schematic diagram of solution‐processed precursor deposition and the growth procedure of MoS2–WS2 in‐plane heterostructures. b–d) OM image of a scalable MoS2–WS2 heterostructure and the corresponding Raman mapping of the E′ mode of MoS2 and the A′1 mode of WS2. a–d) Reproduced with permission.[¹³²] Copyright 2019, American Chemical Society. e) Schematic illustration showing the synthesis of MoS2–WS2 lateral heterostructures. f) Optical micrograph of an as‐grown heterostructure. g,h) PL results from different regions and Raman mapping in (f). e–h) Reproduced with permission.[¹⁷⁶] Copyright 2018, Elsevier. Scale bars: 50 µm (b–d).
… 
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Review
Two-Dimensional Metal Chalcogenide Heterostructures:
Designed Growth and Emerging Novel Applications
Dongyan Li, Zexin Li, Ping Chen, Lejing Pi, Nian Zuo, Qiaojun Peng, Xing Zhou,*
and Tianyou Zhai*
DOI: 10.1002/admi.202100515
the typical semiconducting characteris-
tics, many intriguing physical properties,
such as Hofstadter’s butterfly pattern,[42–44]
quantum Hall eects,[44] and new Dirac
points[45] in 2D heterostructures, are
related to the interlayer coupling. With the
fascinating properties of 2D heterostruc-
tures, recent studies have shown their
transformative advances in electronics
and optoelectronics.[18,46–52] Furthermore,
superlattices have also gained much atten-
tion, including moiré superlattices and
multiheterostructures.[53–85] Among them,
2D metal chalcogenides represent a class
of ideal materials for the synthesis of
2D heterostructures due to their tunable
bandgap from semiconductors to topolog-
ical insulators, strong light–matter interac-
tions,[64,65] and multifunctional structures
via artificial construction.[86–89]
To date, the fabrication of 2D metal chalcogenide hetero-
structures (2DMCHs) is generally achieved by mechanical
transfer.[5,90–101] The mechanical transfer is the most straight-
forward and natural approach to construct vertical 2DMCHs.
However, the products are often contaminated, with random
and small crystal sizes, and low throughput.[102] Besides, this
method is hard to fabricate lateral heterostructures limited by
the transfer approaches.[103] On the other hand, chemical vapor
deposition (CVD) has been proposed to be an ecient way to
grow high-quality vertical heterostructures or lateral hetero-
structures with a well-controlled size and thickness by changing
experimental conditions, as well as the large-scale growth,
which is compatible with the integration technology.[104–122]
Recently, the designed growth of 2DMCHs has been developed
rapidly through modulating the source supply, gas transport,
and substrate engineering.[109,123–126] Besides, emerging novel
applications based on 2DMCHs such as memory, infrared (IR)
photodetection, and superlattice have been developed rapidly in
recent years.[18,127,128]
In view of this, we aim to present a comprehensive review of
recent progress in the controllable CVD synthesis and emerging
novel applications of 2DMCHs. First, we give a brief introduc-
tion of the fundamental mechanism of the CVD process and
then summarize the main factors of CVD growth to optimize
the quality further. Second, we provide three controlled growth
strategies of 2DMCHs, including additives-assisted process,
substrate engineering, and mass transfer process (Figure 1).
Moreover, the extraordinary devices and physical phenomena
There has been a renewed interest in 2D metal chalcogenide heterostructures
(2DMCHs) in the context of their exceptional optoelectronic properties
and potential for a wide variety of practical applications. However, the
controllable synthesis of 2DMCHs remains a huge challenge. Recently,
chemical vapor deposition (CVD) has been proposed to be an ecient way to
realize high-quality, large-scale, and layer-controllable 2D materials and has
also shown high feasibility in 2DMCHs. Here, the latest controllable CVD
growth strategies of 2DMCHs are introduced. The designed growth techniques
mainly focus on three vital factors in CVD: source supply, mass transport, and
substrate engineering. Then, the emerging novel applications of 2DMCHs
are also systematically reviewed with particular attention to memory, infrared
photodetector, and moiré superlattice, which have demonstrated significant
progress in recent years. Finally, future opportunities and remaining challenges
concerning the developments of 2DMCHs are presented.
D. Y. Li, Z. X. Li, Dr. P. Chen, L. J. Pi, N. Zuo, Q. J. Peng, Prof. X. Zhou,
Prof. T. Y. Zhai
State Key Laboratory of Materials Processing and Die & Mould Technology
School of Materials Science and Engineering
Huazhong University of Science and Technology (HUST)
Wuhan 430074, P. R. China
E-mail: zhoux0903@hust.edu.cn; zhaity@hust.edu.cn
Prof. X. Zhou
State Key Laboratory of Crystal Materials
Shandong University
Jinan 250100, P. R. China
The ORCID identification number(s) for the author(s) of this article
can be found under https://doi.org/10.1002/admi.202100515.
1. Introduction
2D heterostructures, formed by stacking vertically or stitching
seamlessly diversified 2D layered materials (2DLMs), are a
current research hotspot due to their extraordinary proper-
ties and potential for functional devices beyond traditional
3D materials.[1–35] In general, 2D heterostructures are com-
posed of 2DLMs, which exhibit many exceptional electrical and
optical characteristics such as quantum confinement, strong
light–matter interaction, and artificially tunable band align-
ments.[36–41] In particular, there are fully saturated chemical
bonds on the surface of 2D materials, allowing them to be easily
combined into heterostructures with high-quality interfaces
releasing the strictly lattice mismatching requirement. Beyond
Adv. Mater. Interfaces 2021, 8, 2100515
... Among diverse 2D transition metal-based components, metal chalcogenides exhibit different anisotropic characteristics ranging from electrochemical, electron mobility to magnetism, intercalation, catalytic and redox properties [18][19][20]. So far, several transition metal chalcogenide nanostructures were prepared via chemical vapour deposition [21,22], chemical/mechanical exfoliation [23,24], wet chemical [25] and hydrothermal approaches [26,27]. Whereas, expensive bottom up and case-by case deviations in top-down methods limiting their bulk scale, homogeneity and further substrate removal causes additional cost. ...
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... 115 183 have also been achieved recently using the multistep sequential CVD growth process. 552 For sequential growth, the nucleating primary block (e.g., WS 2 ) was placed at the downstream end, and the powder source of the selected secondary block (WO 3 and Se for WSe 2 ) was heated for evaporation under the carrier gas (e.g., Ar) at the upstream end. The edges of the primary block acted as a lateral epitaxy provider for continued lateral growth, whereas the basal plane acted as a vdW epitaxy provider for vertical heterostructure formation at the downstream end of the CVD furnace. ...
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... To comprehend the growth of two different crystals, it is important to understand the kinetics. Modiffusion limited growth mechanism is proposed where the competition between Mo and C adatoms along the edges and surfaces determines the morphology of grown crystals as explained in TMD growth [12,[32][33][34]. It is important to consider the difference in CVD growth schemes of TMDs and current sandwich approach. ...
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