Introduction to Two-Dimensional Materials

Abstract

The application areas of two-dimensional (2D) materials, their heterostructures and composites are rapidly expanding — thanks to their extraordinary mechanical, optical, electronic and thermal properties. The family of 2D materials, which are finding a use in applications, is rapidly growing, and now includes graphene, graphene oxide, hexagonal boron nitride and transition-metal dichalcogenide, as well as the recently obtained chemical derivatives, physically modified hybrids and allotropes. New applications also trigger the development of new and more efficient methods for the synthesis of 2D materials and the formulation of composites. In this paper, we focus on the relation between the structure of the 2D materials and their heterostructures on the one hand and their properties on the other, summarize recent improvements in the synthesis approaches and discuss the perspectives in applications. We highlight existing applications in electronics, optoelectronics, electrocatalysis and energy storage and discuss new potential areas such as functional coatings and biomedical materials and devices.

The role of 2D material families in energy harvesting: An editorial overview

“…1 shows the schematic structures of typical 2D materials which are used to make composites with different materials.

Figure 1 Schematic of typical 2D materials applied in energy storage devices [ 10 ].

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Graphene/Ge Photoconductive Position-Sensitive Detectors Based on the Charge Injection Effect

“…Two-dimensional materials are those in which electrons can move freely in only two dimensions, including graphene, black phosphorus, and transition metal dichalcogenides [ 14 ]. Two-dimensional materials have exhibited unique optical and electrical properties, including high carrier mobility, tunable band structure, and strong light-matter interaction, which make them widely used in the preparation of optoelectronic devices.…”

Impact of Preprocessing of Graphene Additive via Ultrasonication on the Electrochemical Performance of Activated Carbon‐Based Supercapacitors

“…[ 20 ] Graphene's positive role in composite materials is related to its high electrical conductivity (10 8 S m −1 for pure graphene) [ 21 ] and thermal conductivity, [ 22 ] large surface area (2630 m 2 g −1 ), [ 23,24 ] chemical neutrality, [ 25 ] and environmental friendliness, [ 26 ] which all originate from its unique electronic structure. [ 27 ]…”

“…[20] Graphene's positive role in composite materials is related to its high electrical conductivity (10 8 S m À1 for pure graphene) [21] and thermal conductivity, [22] large surface area (2630 m 2 g À1 ), [23,24] chemical neutrality, [25] and environmental friendliness, [26] which all originate from its unique electronic structure. [27] Despite the excellent role of graphene in composite EDLC electrodes, one of the challenges that still remains unsolved is the influence of the compositing method of graphene with AC on the electrochemical properties. As an example, Chen et al [11] reported the fabrication of AC/graphene composite by mixing and annealing a mixture of graphene oxide, KOH, and AC at 800 °C in a furnace under an inert atmosphere.…”