Carbon-Phosphide Monolayer with High Carrier Mobility and Perceptible I-V Response for Superior Gas Sensing
Monolayered carbon phosphide (CP) with semi-metallic electrical conductivity and graphene-like Dirac cone response, has attracted significant attention to advanced nanoelectronics community, gas sensing devices. The CP monolayer exhibits a semi-metallic behavior in the x-direction and a semiconducting behavior in the y-direction. With the presence of graphene-like Dirac cones, it holds highly anisotropic carrier mobility characteristics. Here, we introduce the first-principle theoretical calculations for understanding the adsorption mechanism of different gas molecules, CO, CO2, NH3, NO and NO2 monolayer based electronic sensing devices. The binding strengths of these gas molecules adsorbed on the CP layer are much stronger than other reported 2D materials, such as graphene, blue phosphorene, germanene, etc. Additionally, the charge transfer analysis also supported an enhanced binding strength due to the sufficient amount of charge sharing between CP monolayer and gas molecules. We further present an extensive study about the transport properties of CP monolayer sensor device with electrodes made out of identical material. The transmissions characteristics, the density of states, and I-V response supported by analysis of charge distribution of CP monolayer by adsorption of CO, CO2, NH3, NO, and NO2. molecules have been calculated by using density functional theory (DFT) and non-equilibrium Green’s function (NEGF). Presented theoretical investigations reveal CP monolayer-based device exhibits improved characteristics and could lead the foundation towards constructing the highly sensitive nanosensor devices.