A New, Thorough Look on Unusual and Neglected Group III‐VI Compounds Toward Novel Perusals

Abstract

been permitted. [4][5][6][7] Although, the employment of 2D nanosheets, especially in biomedicine, is still in its primordial state and has permitted to the realization of novel advancements in such applications. [8][9][10] It needs to be highlighted that some of these compounds present mild cytotoxicity and dose-dependent induced metabolic disadvantages. [11,12] Albeit direct use in the body is not yet advisable, it is possible to indirectly employ these compounds in the creation of wearable devices for tracking vital parameters. [13] Research on such topics, both from fundamental and applied studies has led to an exponential increase in the number of publications during the last 10 years (Figure 1c). [14] One of the pivotal characteristics of 2D nanostructures is their high specific area-to-thickness ratio, which can be easily modulated through delamination processes. [15] Ultimately, the smallest crystals that can be created are mono-or bi-atomic layers. To understand how the nanocrystals form from bulk, it is important to comprehend the main characteristic features of the macrocrystals. A layered crystal lattice is presented in Figure 2. These crystals are governed by strong, covalent (or ionic) in-plane bonds, which are often arranged into hexagonal honeycombs. These individual sheets are linked together by inter-plane (inter-layer), and weak van der Waals (vdW) forces. The bond energies between the in-plane atoms, are the major contribution on the total energy of the lattice, leaving weak inter-plane interactions with relatively large distances (i.e., about few hundred picometers in graphene). These large inter-planar spaces are suitable attack points for size reduction, [16][17][18] which requires an external energy input from a providing source in order to delaminate single-layer crystals.The in-plane honeycomb structure is responsible for electrical transport and associated phenomena. For instance, the great mobility of p-electrons and their delocalization on the surface allows excellent transport in graphene. [23,24] However, in some other electro-and photoactivated semiconductors based on 2D materials, the electrical transport on the surface is responsible for the hole-electron confinement. [25] It can also produce poor electrical conduction by 2D materials such as hexagonal boron nitride (hBN) and so making them electrical insulators (see Figure 1a). [26] These differences in the layersThe attention on group III-VI compounds in the last decades has been centered on the optoelectronic properties of indium and gallium chalcogenides. These outstanding properties are leading to novel advancements in terms of fundamental and applied science. One of the advantages of these compounds is to present laminated structures, which can be exfoliated down to monolayers. Despite the large knowledge gathered toward indium and gallium chalcogenides, the family of the group III-VI compounds embraces several other noncommon compounds formed by the other group III elements. These compounds present various crystal lattices...

Exploring the electronic, optical, and thermoelectric features of BaXCu3Se4 (X = In, Tl) quaternary chalcogenides: first-principles study

“…It may also be observed in the optical and electronic absorption properties. Thallium and indium also can act as dopants for the charge carriers that are introduced into the crystal lattice, changing the conductivity and the optical features of these material [59]. For several applications, including the optoelectronics, the effects of doping are vital to modify the electronic and optical features of BaInCu 3 Se 4 and BaTlCu 3 Se 4 .…”