First-Principles Study of Sulfur Dioxide Sensor Based on Phosphorenes

The adsorption behaviors of sulfur dioxide (SO
₂
) gas molecule over pristine, boron-, silicon-, sulfur-, and nitrogen-doped phosphorenes are theoretically studied using first-principles approach based on density-functional theory. The adsorption energy (E
_a
), adsorption distance (d), and Mulliken charge (Q) of SO
₂
molecules adsorbed on the different phosphorenes are calculated. The simulation results demonstrate that pristine phosphorene is sensitive to SO
₂
gas molecule with a moderate adsorption energy and an excellent charge transfer, while evidence of negative effect is observed during doping with S and N. We also observe that B- or Si-doped phosphorene exhibits extremely high reactivity toward SO
₂
with a stronger adsorption energy, indicating that they are not suitable for use as SO
₂
sensors, but have potential applications in the development of metal-free catalysts for SO
₂
. Therefore, we suggest that pristine phosphorene could be an excellent candidate as sensor for the polluting gas SO
₂
.