Atomically engineered black phosphorene nanosheets for selective detection of ovarian cancer VOC biomarkers

Abstract

Early-stage diagnosis of ovarian cancer is critically limited by the absence of sensitive, non-invasive screening technologies. The analysis of disease-associated VOCs in exhaled breath is a promising diagnostic route; however, success depends on sensor materials that can differentiate chemically similar analytes with high precision. This work focuses on developing a nanoscale sensing platform with enhanced sensitivity and reliable selectivity for key ovarian cancer VOC biomarkers, including 2-butanone, decanal, and nonanal. To uncover the sensing mechanism and assess stability against interfering gases (H₂O and CO₂), we used van der Waals corrected DFT+NEGF transport calculations to analyse the adsorption behaviour and electronic response on metal-functionalized black phosphorene. We found that pristine black phosphorene interacts only weakly with the VOCs, exhibiting low adsorption energies (E_ads) that limit its practical sensing capability. In contrast, metal functionalization with Au, Ag, and Cu markedly enhances molecular binding. Among all configurations, Cu@BP shows the strongest affinity, with adsorption energies of −0.82 eV for 2-butanone, −0.68 eV for decanal, and −0.65 eV for nonanal, respectively. Charge-transport analysis demonstrates that Cu-decorated black phosphorene exhibits a markedly enhanced sensing response, with conductance modulation reaching 84–100%, whereas pristine black phosphorene shows only modest variations in the range of 4–48%. The rapid recovery at room temperature further confirms the reusability and excellent reversibility of the sensor. Overall, these findings demonstrate that Cu-decorated black phosphorene is a viable nanosensor for the selective detection of ovarian cancer-associated VOC biomarkers through breath analysis.