2D MoS₂ for detection of COVID-19 biomarkers – a first-principles study

Abstract This study investigates specific compounds in the breath that can indicate COVID-19 and lung cancer. Heptanal (C 7 H 14 O), acetone (C 3 H 6 O), propanol-1 (CH 3 CH 2 CH 2 OH), butanal (C 3 H 7 CHO), isopropanol (CH 3 CHOHCH 3 ), acetaldehyde (CH 3 CHO), 2,4-octadiene (C 8 H 14 ), and ethyl butyrate (C 6 H 12 O 2 ) were studied. We analyze how these compounds interact using two-dimensional (2D) 2H and SV-MoS 2 monolayers through first-principles calculations. Van der Waals forces bind all VOCs on the MoS 2 surface in vacuum and humid conditions. The decrease in the band gap of the MoS 2 -VOC complex in these environments enhances sensitivity. The complexes of 2,4-octadiene, propanol-1, and ethyl butanoate are more conductive because their work function is lower, and their V(z) shift is more significant. The adsorption isotherm demonstrates the potential for surface reuse in sensing applications. The study confirms high sensitivity (>85%) and fast recovery time (up to 70 femtoseconds) for detecting in visible (VL) and ultraviolet (UV) regions. Mainly, 2,4-octadiene exhibits high sensitivity and selectivity. In conclusion, the 2H and SV MoS 2 monolayers effectively detect COVID-19 and lung cancer markers in vacuum and humid conditions.