Black Phosphorene with AU Modification: Oxynitride Remover and Hydrogen Sensor

Abstract

Effective detecting toxic gases and the clean energy hydrogen is urgently necessary in industrial production and our daily life. Here, the sensing properties of Au-adsorbed/doped black phosphorene monolayer towards six different gases (CO, H2, H2S, NO, NO2, and SO2) are theoretically investigated through density functional theory in combination with the non-equilibrium Green’s function approach. We demonstrate that the Au-adsorbed black phosphorene monolayer interacts with the toxic gases stronger than the Au-doped black phosphorene. The calculated adsorption energy, the charge transfer, the electron localization function, the band structure, and the density of states indicate that the Au-adsorbed/doped black phosphorene exhibits strong and sensitive chemisorption to NOx gases. Surprisingly, the Au-doped black phosphorene is suitable for detecting H2 molecules, offering a promising solution to H2 sensing. The calculated recovery time and current‒voltage curves reveal that the Au-adsorbed/doped black phosphorene device acts as an ultra-sensitive remover of NOx molecules. Furthermore, the Au-doped black phosphorene sensor achieves a highly sensitive and reusable detection of H2 at room temperature. Our results provide a theoretical basis for the potential applications of the Au-adsorbed/doped black phosphorene in gas-sensing, especially in the desirable NOx remover and H2 sensor.

Keywords: phosphorene, gas-sensing properties, NOx remover, H2 sensor, first-principles calculation.