A Comparative Study of the Electronic Transport and Gas-Sensitive Properties of Graphene+, T-graphene, Net-graphene, and Biphenylene-Based Two-Dimensional Devices

Abstract

The electronic transport properties of the four carbon isomers: graphene+, T-graphene, net-graphene, and biphenylene, as well as the gas-sensing properties to the nitrogen-based gas molecules including NO 2 , NO, and NH 3 molecules, are systematically studied and comparatively analyzed by combining the density functional theory with the nonequilibrium Green's function. The four carbon isomers are metallic, especially with graphene+ being a Dirac metal due to the two Dirac cones present at the Fermi energy level. The two-dimensional devices based on these four carbon isomers exhibit good conduction properties in the order of biphenylene > T-graphene > graphene+ > netgraphene. More interestingly, net-graphene-based and biphenylene-based devices demonstrate significant anisotropic transport properties. The gas sensors based on the above four structures all have good selectivity and sensitivity to the NO 2 molecule, among which T-graphene-based gas sensors are the most prominent with a maximum ΔI value of 39.98 μA, being only three-fifths of the original. In addition, graphene+-based and biphenylene-based gas sensors are also sensitive to the NO molecule with maximum ΔI values of 29.42 and 25.63 μA, respectively. However, the four gas sensors are all physically adsorbed for the NH 3 molecule. By the adsorption energy, charge transfer, electron localization functions, and molecular projection of self-consistent Hamiltonian states, the mechanisms behind all properties can be clearly explained. This work shows the potential of graphene+, T-graphene, net-graphene, and biphenylene for the detection of toxic molecules of NO and NO 2 .

Transition Metal (Co, V, W, Zr) Single-Atom Decorated Biphenylene for Enhancing the Sensing Performance of SF6 Decomposition Molecules

“…Despite the great progress in studying the electronic structure of the BPN monolayer, the sensing performance of BPN-based nanodevices and the effects of metal doping and adsorption are still ambiguous compared to other 2D carbon materials . Therefore, with its excellent physical and chemical properties, BPN is expected to be used in gas sensors that can effectively recognize gas composition and concentration, which is considered to be a good candidate for future toxic gas sensors. − In this paper, we demonstrate the kinetic and thermodynamic stability of the BPN based on first-principles calculations, phonon spectra without imaginary frequencies, and undeformed molecular dynamics, with a large overlap of the conduction and valence bands at the Fermi level with a remarkable class II Dirac cone, revealing that the BPN is metallic. , Due to its excellent performance, it has been studied and applied to gas sensors that can effectively recognize the composition and concentration of gases. As one of the most important pollutants in thermal and chemical power plants, SF 6 is widely used as a new generation of ultrahigh-voltage insulating medium for electrical and electronic equipment.…”

Highly Sensitive Gas Sensor for Detection of Air Decomposition Pollutant (CO, NOx): Popular Metal Oxide (ZnO, TiO2)-Doped MoS2 Surface

“…In recent years, the gas component analysis method represented by SF 6 decomposition component detection has become a research hotspot at home and abroad. − Inspired by the above research, the detection of air decomposition components under PD is proposed to realize the detection and diagnosis of insulation faults of air switchgear. There are many cases where scholars in the field of theoretical chemistry have explored gas-sensitive materials for CO, NO, and NO 2 gases. − However, most of the cases have studied only one or two of these gases. There are fewer cases in which gas-sensitive materials for these three gases have been explored simultaneously in the context of PD faults in air switchgear.…”

Phosphorus-doped T-graphene nanocapsule toward O3 and SO2 gas sensing: a DFT and QTAIM analysis

“…The numerous bonding modes of carbon (C) atoms, which are widely dispersed in nature, allow them to form a broad variety of allotropes with distinct physical and chemical characteristics, including diamond carbon nanotubes, fullerene, graphene, and so on 8 . However, for toxic gas detection, pure graphene is too chemically inert and insensitive to be of much value 2 , which led the researchers to study the sensitivity of various allotropes of C in both pristine and doped states for gas sensing applications 8 – 15 . P-doped graphene showed strong chemisorption of SO 2 , NO 2 , O 2 , etc.…”

“…Very few studies on T-graphene's applications have been reported yet. T-graphene has shown high potential for gas sensing and ion storage applications 8 , 18 , 19 . Xie et al reported T-graphene to be a potential candidate for NO and NO 2 detection 8 .…”

“…T-graphene has shown high potential for gas sensing and ion storage applications 8 , 18 , 19 . Xie et al reported T-graphene to be a potential candidate for NO and NO 2 detection 8 . Li-doped T-graphene is reported to be a promising material for H 2 adsorption and storage 19 .…”