<p>The presence of chemical nerve agents (CNAs) poses significant threats to both living beings and the environment, making their rapid detection and elimination crucial. In this study, the potential of boron carbide (B₁₆C₁₆) nanocage (BCN) as an electrochemical sensor material for A-series chemical nerve agents (CNAs) was investigated using density functional theory (DFT). The adsorption studies reveal the chemisorption nature of interactions between CNAs and BCN, characterized by high negative adsorption energies for A230@SiteC (-95.136&#xa0;kcal/mol), A232@SiteA (-31.792&#xa0;kcal/mol), and A234@SiteB (-92.963&#xa0;kcal/mol). FMO studies reveal that the energy gaps of 1.40&#xa0;eV for A230@SiteC, 1.61&#xa0;eV for A232@SiteC, and 1.46&#xa0;eV for A234@SiteB decreased from 1.80&#xa0;eV of pristine BCN. The Fermi level energy (E_FL) undergoes significant shifts in all systems, depending on the density of states (DOS). Topological analyses, including QTAIM and NCI, indicate that the interactions are predominantly of weak covalent or van der Waals nature. The adsorption of CNAs significantly enhances the electrical properties, with electrical conductivity (<i>σ</i>) increasing to 5.98 × 10¹² S/m (A-230@SiteC), 5.73 × 10¹² S/m (A-232@SiteC), and 5.92 × 10¹² S/m (A-234@SiteB). The decrease of work function (<InlineEquation ID="IEq1"> <EquationSource Format="TEX">\(\phi\)</EquationSource> <EquationSource Format="MATHML"><math> <mi>ϕ</mi> </math></EquationSource> </InlineEquation>) and short recovery times (<i>τ</i>) in these configurations increases the sensing response (S) 0.0823 for A-230@SiteC, 0.0376 for A-232@SiteC, and 0.0705 for A-234@SiteB. These results highlight the efficiency of BCN as a robust sensor for CNAs, making it a promising candidate for future advancements in chemical sensing technologies.</p> Graphical abstract <p></p>