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Polymorphism in Post-Dichalcogenide Two-Dimensional Materials.
Hadallia Bergeron1, Dmitry Lebedev1, Mark C Hersam1,2,3
1Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States.
Exploring polymorphism in emerging two-dimensional (2D) materials, this review details their diverse structures, properties, and control methods. Polymorph engineering offers a pathway for designing novel 2D materials with tailored functionalities.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Two-dimensional (2D) materials possess diverse atomic structures and properties.
- Polymorphism, the existence of different crystal structures for a given composition, is key to unlocking new functionalities in 2D materials.
Purpose of the Study:
- To identify polymorphs in emerging 2D materials beyond traditional ones.
- To describe how properties depend on specific polymorphs.
- To outline methods for controlling polymorphism in 2D materials.
Main Methods:
- Comprehensive survey of recent experimental and theoretical literature.
- Focus on post-dichalcogenide 2D materials: elemental groups III, IV, V; layered metal chalcogenides; and transition metal halides.
Main Results:
- Identification of various polymorphs in emerging 2D material classes.
- Description of polymorph-dependent property variations.
- Overview of synthesis and characterization techniques for controlling 2D material polymorphism.
Conclusions:
- Polymorphism is a critical factor in the design of novel 2D materials.
- Engineering 2D material polymorphs enables "materials by design" approaches.
- Future research should focus on exploiting polymorphism for advanced functionalities.
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