MoB₂: a new multifunctional transition metal diboride monolayer

Abstract

Several layered transition metal borides can now be realized by a simple and general fabrication method [Fokwa et al., Adv. Mater. 2018, 30, 1704181], inspiring our interest to transition metal borides monolayer. Here, we predict a new two-dimensional (2D) transition metal diboride MoB2 monolayer (ML) and study its intrinsic mechanical, thermal, electronic, and transport properties. The MoB2 ML has isotropic mechanic properties along the zigzag and armchair directions with a large Young's stiffness, and has an ultralow room-temperature thermal conductivity. The Mo atoms dominate the metallic nature of MoB2 ML. It shows an obvious electrical anisotropy and a current-limiting behavior. Our findings suggest that MoB2 ML is a promising multifunctional material used in ultrathin high-strength mechanical materials, heat insulating materials, electrical-anisotropy-based materials, and current limiters.It is helpful for the experimentalists to further prepare and utilize the transition metal diboride 2D materials.

V2CTx and Ti3C2Tx MXenes Nanosheets for Gas Sensing

“…Only Cl atoms without F exist on the surface of Cl−Ti 3 C 2 T x . Therefore Li−V 2 CT x and Na−V 2 CT x have weak negative responses to It is also noted that these devices show a linear behavior in most cases, but a nonlinear behavior appears only under some high biases due to the damped electron transmission 51 and/or quantum confinement for many two-probe device systems. 33,53 5.…”

“…To theoretically understand the gas-sensing of MXenes, the transport properties of monolayer V 2 CT x were analyzed by the DFT-NEGF method and a two-probe device model (see Figure ), which is quite useful to visualize the change of conductivity (i.e., the slope of I–V curve) on the device level. − Considering that the “T” element in V 2 CT x is dominantly occupied by the “O” element after rinsing and storing, , we first evaluated the I–V curves of the monolayer V 2 CO 2 before and after NH 3 adsorbing, and as shown in Figure b the magnitude of current passing through the sensor along the zigzag direction is about 3 times as large as that along the armchair direction. Clearly, after adsorbing ammonia on V 2 CO 2 (denoted as NH 3 /V 2 CO 2 ), the decreased slopes of the I–V curves suggest a lowered conductivity and an enhanced resistance relative to the clean V 2 CO 2 .…”

Multifunctional Lateral Transition‐Metal Disulfides Heterojunctions

“…After the discovery of the well-known graphene, [1] a large number of two-dimensional (2D) monolayers (MLs) have been fabricated and studied, including silicene, [2,3] h-BN, [4] transition metal sulfides, [5][6][7][8][9][10] phosphorene, [11][12][13][14][15] MXene, [16,17] borophene, [18][19][20][21][22][23] stanene, [24] antimonene, [25] g-C3N4, [26,27] ferromagnets, [28,29] chromium trihalides CrX3, [30][31][32][33] and other graphene-like MLs. [34][35][36][37] Each type of these 2D materials possesses unique properties in mechanics, thermodynamics, optics, electrics, and magnetism.…”

Two-Dimensional TeB Structures with Anisotropic Carrier Mobility and Tunable Bandgap

“…The two structures α-TeB and β-TeB maintain structural integrity up to 1000 K and 700 K, respectively. It is clear that the thermodynamic stability of the α-TeB structure is higher than that of hex-GaB6 and rect-InB6 are both stable at 500 K, and hex-InB6 only retains integrity under 300 K, MoB2 is stable at 500 K [64]. The well-maintained geometries at 700 K or 1000 K indicate that α-TeB and β-TeB can not only be applied at room temperatures but might also have possible applications at a relatively high temperature.…”