Two-dimensional pnictogens: A review of recent progresses and future research directions

Abstract

Soon after the synthesis of two-dimensional (2D) ultrathin black phosphorus and fabrication of field effect transistors thereof, theoretical studies have predicted that other group-VA elements (or pnictogens), N, As, Sb, and Bi can also form stable, single-layer (SL) structures. These were nitrogene in a buckled honeycomb structure, arsenene, antimonene, and bismuthene in a buckled honeycomb, as well as washboard and square-octagon structures with unusual mechanical, electronic, and optical properties. Subsequently, theoretical studies are followed by experimental efforts that aim at synthesizing these novel 2D materials. Currently, research on 2D pnictogens has been a rapidly growing field revealing exciting properties, which offers diverse applications in flexible electronics, spintronics, thermoelectrics, and sensors. This review presents an evaluation of the previous experimental and theoretical studies until 2019, in order to provide input for further research attempts in this field. To this end, we first reviewed 2D, SL structures of group-VA elements predicted by theoretical studies with an emphasis placed on their dynamical and thermal stabilities, which are crucial for their use in a device. The mechanical, electronic, magnetic, and optical properties of the stable structures and their nanoribbons are analyzed by examining the effect of external factors, such as strain, electric field, and substrates. The effect of vacancy defects and functionalization by chemical doping through adatom adsorption on the fundamental properties of pnictogens has been a critical subject. Interlayer interactions in bilayer and multilayer structures, their stability, and tuning their physical properties by vertical stacking geometries are also discussed. Finally, our review is concluded by highlighting new research directions and future perspectives on the challenges in this emerging field.

Emerging Mono‐Elemental Bismuth Nanostructures: Controlled Synthesis and Their Versatile Applications

“…In recent years, 2D pnictogen, group‐VA atomic sheet (phosphorene, arsenene, antimonene, and bismuthene) have achieved remarkable progress and is considered to be a competitive candidate for next‐generation logic devices due to their fascinating physicochemical properties, such as tunable bandgap and controllable stability except arsenene because of its high toxicity. [ 1–3 ] Until now, many comprehensive and impressive reviews have been published on topics related to phosphorene, [ 4–9 ] and antimonene. [ 10 ] For example, Zhang and co‐workers [ 5 ] systematically summarized the recent developments in black phosphorus (BP), including the synthetic approaches for fabricating single or few‐layer BP, the recent advances in its optical, electronic, and mechanical properties, and the related devices.…”

Stable, one-dimensional suspended and supported monatomic chains of pnictogens: a metal–insulator framework

“…36 Very little is known about the monatomic chains of pnictogens (N, P, As, Sb, Bi) 34,37,38 despite their 2D monolayers, multilayers and nanoribbons having received growing interest. [39][40][41][42][43][44][45][46][47][48][49][50][51] In fact, 2D mono-and multilayers of pnictogens offer diverse properties to be used in various applications, such as in topological spintronic devices, biosensors, batteries, thermoelectric devices, nonlinear optics etc. For example, P and As monolayers and multilayers are semiconductors and hence become attractive materials in 2D electronics.…”

Xenes as an Emerging 2D Monoelemental Family: Fundamental Electrochemistry and Energy Applications

“…[125,126] Element doping is another important route to induce the formation of defects into the emerging Xenes. [127,128] Borophene was proved to be a promising candidate for future nanoelectron devices and advance rechargeable battery, [129,130] because borophene is intrinsically metallic [91] and endows high free charge carrier concentration, [93] high Young's modulus (398 GPa nm), and bending flexibility. [131] Borophene has also displayed amusing Dirac transportation performance, which is confirmed from its high DOS near Fermi level.…”