Graphene Analogues of Inorganic Layered Materials

Abstract

The discovery of graphene has created a great sensation in chemistry, physics, materials science, and related areas. The unusual properties of graphene have aroused interest in other layered materials, such as molybdenum sulfide and boron nitride. In the last few years, single- as well as few-layer as well as chalcogenides and other inorganic materials have been prepared and characterized by a variety of methods. These materials possess interesting properties, and some have potential applications. This Review provides an up-to-date account of these emerging two-dimensional nanomaterials. Not only are the synthesis and characterization covered, but also important aspects such as spectroscopic and optical properties, magnetic and electrical properties, as well as applications. Salient features of the composites formed from the layered inorganic structures with graphene and polymers are presented along with a brief description of borocarbonitrides.

Two-dimensional inorganic analogues of graphene: transition metal dichalcogenides

“…Group theory predicts 2H-MoS 2 to exhibit four first-order Raman modes, E 2 2g , E 1g , E 1 2g and A 1g with frequencies at 32, 286, 383 and 408 cm −1 , respectively [11,72]. E 1 2g and A 1g are the only intense modes which correspond to the in-plane (intralayer) and out-of-plane (interlayer) vibrations, respectively (the inset of figure 7b) [73].…”

“…Important physical methods to synthesize single-or few-layer TMDCs comprise micromechanical exfoliation (scotch-tape technique), liquid-phase exfoliation, laser-thinning and sputtering [4,18]. Mechanical exfoliation provides electronic grade monolayers suitable for high-performance devices and for studies on condensed matter phenomena [11,12,19,20], but is limited to short-scale production. Liquid-phase exfoliation via ultrasonication in a solvent medium provides a route to large-scale production of large-area single-and few layers of a number of layered materials for applications in catalysis and electrochemical storage.…”

“…1 nm [11], (c) adapted with permission from Mahler et al [54] and (d-g) adapted with permission from Yoo et al [55].…”

Functionalization of Two‐Dimensional Transition‐Metal Dichalcogenides

“…The commonly applied techniques include mechanical cleavage, solution-based exfoliation, Chemical Vapor Deposition (CVD), and hydrothermal synthesis. [7,[17][18][19][20][21][22] These strategies for TMD nanosheet production allow for deep investigation of their layer-dependent properties, and investigations into their future industrial application.…”

“…[6][7][8][9][10][11] This is due to their exciting physical and chemical properties. TMDs have been deemed suitable (and in some cases game-changing) for potential applications in a variety of areas (catalysis, electronics, photonics, energy storage, and sensing).…”