Computational Study of Borophene with Line Defects as Sensors for Nitrogen-Containing Gas Molecules

Abstract

Borophene, a member of two-dimensional (2D) materials, has very important application potential in gas sensing because of its large surface area and rich electronic properties. Very recently, the intrinsic line defects in β 12 and χ 3 borophenes have been observed experimentally. In this work, by means of density functional theory computations coupled with the nonequilibrium Green's function (NEGF) method, we explored the potential applications of 2D borophene with two different kinds of line defects in gas sensing. It is found that the nitrogen-containing gas molecules such as NO, NO 2 , and NH 3 can be strongly adsorbed on the line defects of borophene with considerably high adsorption energies. Remarkably, according to the transmission coefficient and I−V characteristics, the adsorption of these nitrogen-containing gas molecules can induce significant change in the current of defective borophene even at rather low biases. Especially, the degree of current change strongly depends on the type of adsorbed molecules. The extraordinary sensitivity and selectivity suggest that it is possible to design nitrogen-containing gas sensors based on borophene with line defects.

Borophene: Two-dimensional Boron Monolayer: Synthesis, Properties, and Potential Applications

“…Defect engineering and heteroatomic doping provide promising pathways for enhancing the gas-sensing performance of borophene. The effects of line defects in β 12 and χ 3 borophenes on their gas-sensing performance have recently been studied by coupling DFT computation with nonequilibrium Green’s function method . Nitrogen-containing gas molecules, such as NO, NO 2 , and NH 3 , could strongly adsorb on the line defects of borophene with rather high adsorption energies.…”

“…For application in lithium–sulfur (Li–S) batteries, creating defects on borophene has been proposed as an effective way for enhancing its storage performance due to the minimized passivation of the Li anode . Furthermore, borophene has been theoretically shown to exhibit potential for the detection of gases, such as HCN and ethanol (C 2 H 6 O), due to the existence of a significant charge transfer from gas molecules to borophene or atomic bonding between gas molecules and B atoms. , The incorporation of defects as well as heterostructuring of borophene with other 2D materials provided potential solutions for enhancing its sensing performance toward gases, such as carbon monoxide (CO), nitrogen oxides (NO x ), ammonia (NH 3 ), etc. , …”

“…67,68 The incorporation of defects as well as heterostructuring of borophene with other 2D materials provided potential solutions for enhancing its sensing performance toward gases, such as carbon monoxide (CO), nitrogen oxides (NO x ), ammonia (NH 3 ), etc. 69,70 Freestanding or metal-supported borophenes have been theoretically studied as potential catalysts for hydrogen evolution reaction (HER), which is one of the main reactions in water splitting technology for producing clean hydrogen (H 2 ) energy. 71 2D B monolayers with numerous active sites in the basal plane have been shown to be highly active for HER, with free energy of hydrogen adsorption (ΔG H ) close to zero.…”

Borophene as a rising star in materials chemistry: synthesis, properties and applications in analytical science and energy devices

“…The DFT simulation study was carried out on the adsorption abilities of the N-containing gas molecules on borophene. 89 For sensing inorganic small molecules in the environment, borophene was modified with MoS 2 for the sensing of the gas (NH 3 ) molecule due to its high anisotropic properties. The transport characteristics of the b12 borophene on the MoS 2 substrate for gas sensing were investigated using the NEGF technique.…”

“…This figure has been reproduced from ref. 89 with permission from American Chemical Society, copyright 2020.…”