Blue (Buckled) Versus Black (Puckered) Phosphorene Monolayers for Sensing Biomarkers Associated with Respiratory Diseases – A DFT Study

This study investigates puckered (black) and buckled (blue) phosphorene for sensing volatile organic compounds (VOCs) linked to respiratory diseases. The semiconducting nature of both forms is confirmed by their bandgap and density of states. Heptanal shows the most adsorption in both monolayers. AIM analyses indicated the physisorption of VOCs, while the planar average potential and minimum work function suggest surface charge interactions. Blue phosphorene demonstrated high sensitivity (92.67% to 99.99%) for VOCs, compared to black phosphorene's 0.78% to 74.55%. Blue phosphorene also has a rapid recovery rate of 18 ps in the ultraviolet region. The Langmuir adsorption isotherm model indicates that under humid conditions, Blue phosphorene shows maximum surface coverage (θ) for biomarkers over vacuum media. Blue phosphorene demonstrates remarkable sensitivity toward all the volatile organic compounds (VOCs), including benzaldehyde, 2‐butanone, heptanal, and tetrahydrofuran, which makes it a promising material for sensing biomarkers associated with respiratory diseases. Overall, Buckled (blue) phosphorene is a better VOCs sensor material than puckered (black) phosphorene.