Small molecule gas adsorption onto blue phosphorene oxide layers

We report a first-principles study of the electronic and optical properties of BPO (Blue phosphorene oxide) and BPO-V (Blue phosphorene oxide with vacancy) with the adsorption of low molecular weight gases (CH₄, CO₂, CO, SO₂, and O₂). Blue phosphorene oxide -with and without vacancies- shows different optoelectronic compared to blue phosphorene. The BPO has proven to be more energetically, and structurally stable than blue phosphorene under ambient conditions. Our calculations show that: Blue phosphorene oxide -with and without vacancies- exhibits different optoelectronic compared to blue phosphorene. Physical adsorption occurs for all gas molecules. Highest values of adsorption energy are found when the monolayers interact with O₂ and SO₂. This is associated with a modification of conducting nature, which is changed from semiconductor to conductor character, depending on the orientation of adsorbed molecules. By contrast, the coupling with CO and CO₂ molecules leads to the lowest values of the energy of adsorption. The observed features of the electronic properties and optical response of BPO + adsorbed-gas complexes allow to suggest that this phosphorene-based structures could be promising candidates for gas sensing applications.