Adsorption studies of 2,3-butanedione and acetic acid on ζ-phosphorene sheets based on the first-principles study

Two-dimensional Janus X2STe (X = B, Al) monolayers: the effect of surface selectivity and adsorption of small gas molecules on electronic and optical properties

This investigation delves into the adsorption characteristics of CO, NO, NO2, NH3, and O2 on two-dimensional (2D) Janus group-III materials, specifically Al2XY and B2XY. The examination covers adsorption energies and heights, diverse adsorption sites, and molecular orientations. Employing first-principles analysis, a comprehensive assessment of structural, electronic, and optical properties is conducted. The findings highlight NO2 as a prominent adsorbate, emphasizing the Te surface of 2D Al2STe and B2STe materials as particularly adept for NO2 detection, based on considerations of adsorption energy, height, and charge transfer. Additionally, the study underscores the heightened sensitivity of work function changes in the B2STe material. The adsorption properties of all gas molecules, except for NO2, on both materials were determined to be physical. Upon adsorption of the NO2 gas molecule onto the B2STe Janus material, it was observed that the material exhibited weak chemical adsorption behavior, which was confirmed by the adsorption energy, larger band gap change, electron localization function, work function changes and charge transfer from the material. This research provides valuable insights into the gas-sensing potential of 2D Janus materials.

Adsorption studies of camphene and eucalyptol molecules on orthorhombic germanane nanosheet - A first-principles investigation

In the present work, we deployed a novel orthorhombic germanane nanosheet (ortho-GeNS) as a sensing material to detect camphene and eucalyptol molecules, the indoor air pollutants in the ambient environment. In the beginning, the structural and dynamical permanency of ortho-GeNS is confirmed with cohesive energy (-4.164eV/atom) and phonon-band maps. Successively, the electronic features of ortho-GeNS are conferred using band structure along with the projected density of states maps. The energy gap of ortho-GeNS at the hybrid GGA/B3LYP level of theory is computed to be 3.948 eV. Mainly, the adsorption properties of terpinene molecules, namely camphene and eucalyptol on ortho-GeNS are investigated via ascertaining adsorption energy, Mulliken population analysis, and relative band gap variations. Besides, the scope of adsorption energy values (-0.405eVto-0.669eV) exemplifies that the target molecules are physisorbed on ortho-GeNS. Overall results suggested that the ortho-GeNS can be deployed as a worthy chemiresistive sensor to sense indoor air pollutants for monitoring indoor air quality.