2D Materials: From Structures to Functions

Dear Colleagues,

Research in low-dimensional materials has been enjoying extraordinary growth in recent years, increasingly attracting the attention of a multidisciplinary scientific audience both for fundamental science and for technological applications. In particular, the current decade of the 2010s saw the boom of two-dimensional (2D) materials, triggered by pioneering works on graphene in 2004 and subsequent identification, at the beginning of 2010s, of other atomically thin monolayer systems, such as monolayer hexagonal boron nitride (h-BN) and transition metal dichalcogenides (TMDs). Since then, 2D materials and their combination in lateral and vertical heterostructures have been gaining an impressive research interest, accelerated by the availability of an increasingly broad portfolio of 2D candidate materials. The consequent result is the exponential growth in published papers per year, which passed from 139 in 2010 to 3189 in 2018 (see figure below). 2D materials are without doubt one of the most prolific areas of research in the last few years. Due to their thinness, enhanced surface effects, and unprecedented tunable confinement and geometry-related properties, 2D materials constitute a versatile platform for the realization of a new class of functional systems, opening up important applications in very different fields, namely, surface chemistry and (photo)catalysis, DNA nanostructures, biosensors, band–gap engineering, photovoltaics, electronics, photonics, energy storage, harvesting and conversion, nanomedicine, spintronics, and valleytronics. Moreover, van der Waals (vdW) heterostructures have recently emerged as an additional avenue to engineer new properties by stacking 2D compounds in a desired fashion.

Given the widespread contemporary interest in 2D materials, crystals, and compounds, the aim of this Special Issue is to provide an up-to-date international platform that can enable scientists from various disciplines to publish the latest advancements and up-to-date reviews on the following topics:

- Novel approaches for preparation of stable and large-scale 2D crystals: bottom–up direct synthesis methods (e.g., chemical vapor deposition, wet–chemical methods, topochemical synthesis), and top–down exfoliation routes (e.g., micromechanical, ultrasonic, ion-exchange exfoliation);

- New efforts put forward to expand the portfolio of 2D materials to search from for optimal properties, encouraging both high-throughput computational methods and experimental research for synthesis of new 2D crystals;

- Lateral and vertical 2D material heterostructures: characterization, fabrication, and study of related devices;

- Characterization techniques of 2D materials: electronic, optical, mechanical properties, morphological analysis (e.g., SEM, TEM), crystallographic studies, and AFM measurements. Particular attention should be given to the study of crystal properties, and to investigating the influence of measurement conditions (e.g., moisture, ambient gas/2D surface interaction, supporting substrate) on the results from characterization techniques;

- Novel applications of 2D materials in pharmacy, biology, medicine, and green chemistry;

- Light–matter interactions in 2D materials, through excitons and polarons;

- Chemical functionalization of 2D materials;

- Ion beam modifications of 2D materials, plasma induced changes to 2D systems, defect engineering;

- Integration of 2D materials with conventional semiconductors for electronics and optoelectronics;

- Theory and modelling of 2D materials and related devices.

Dr. Giuseppe Prestopino
Dr. Giuseppe Arrabito
Guest Editors

Manuscript Submission Information

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• Green chemistry
• Surface chemistry
• Growth of 2D crystals: bottom–up and top–down strategies
• Characterization techniques: electronic transport, optical, and mechanical properties
• Exfoliation of parent layered compounds
• Nanoscale engineering
• van der Waals 2D materials
• 2D materials
• Lateral heterostructures
• Vertical heterostructures
• Quantum confinement
• Photophysics of 2D compounds