Exploring the adsorption behavior of O-containing VOCs in human breath on a B2N monolayer using DFT simulations

Abstract

We conducted a DFT study of the B₂N monolayer pairing with the O-containing volatile organic compounds (O-containing VOCs) in exhaled breath, viz. acetone, ethanol, methanol, and formaldehyde. The most stable configuration of O-containing VOCs on the B₂N sheet is also considered and compared with the adsorbed H₂O on the desired monolayer. The adsorption energy when both water and O-containing VOC molecules are present shows that the O-containing VOC molecules can be effectively adsorbed on the surface of B₂N while maintaining stability in the presence of water molecules. The adsorption energy values for the most stable acetone/B₂N, ethanol/B₂N, methanol/B₂N, formaldehyde/B₂N, and H₂O/B₂N complexes are −0.50, −0.61, −0.56, −0.87, and −0.41 eV, respectively. The computed recovery time at 300 K for the desired complexes without radiation ranges from 2.6 × 10⁻⁴ to 440 seconds. Using non-equilibrium Green's function, the electrical current is calculated separately as a function of applied bias voltage of 0–2 volts for each O-containing VOC. The percentage increase in the band gap of the desired B₂N sheet is 5, 19, 25, and 35% upon interaction with methanol, formaldehyde, acetone, and ethanol, respectively. These findings highlight the notable sensing capabilities of the desired B₂N sheet when compared to other sensors such as the BC₆N sheet, pristine MoSe₂ monolayer, and phosphorene. Moreover, these findings may have implications for the potential use of B₂N nanosheets for the detection of O-containing VOCs in human breath, enabling early disease diagnosis.