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

We conducted a DFT study of the BN monolayer pairing with the O-containing volatile organic compounds (O-containing VOCs) in exhaled breath, acetone, ethanol, methanol, and formaldehyde. The most stable configuration of O-containing VOCs on the BN sheet is also considered and compared with the adsorbed HO 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 BN while maintaining stability in the presence of water molecules. The adsorption energy values for the most stable acetone/BN, ethanol/BN, methanol/BN, formaldehyde/BN, and HO/BN 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 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 BN 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 BN sheet when compared to other sensors such as the BCN sheet, pristine MoSe monolayer, and phosphorene. Moreover, these findings may have implications for the potential use of BN nanosheets for the detection of O-containing VOCs in human breath, enabling early disease diagnosis.