Enhancing the sensitivity and selectivity of pyrene-based sensors for detection of small gaseous molecules via destructive quantum interference

Graphene-based sensors are exceptionally sensitive with high carrier mobility and low intrinsic noise, have been intensively investigated in the past decade. The detection of individual gas molecules has reported, albeit underlying sensing mechanism is not yet well understood. We focus on adsorption ${\mathrm{NO}}_{2}$, ${\mathrm{H}}_{2}\mathrm{O}$, ${\mathrm{NH}}_{3}$ a molecular junction pyrene core, which can be considered as minimal graphenelike unit. systematically investigate chemiresistive response within framework density functional theory nonequilibrium Greens functions. highlight fundamental role quantum interference (QI) process, we propose it paradigmatic for sensing. Owing to open-shell character its interaction gives rise Fano resonance thereby triggering strongest response, while weaker interactions ${\mathrm{H}}_{2}\mathrm{O}$ result lower sensitivity. demonstrate that by exploiting destructive QI arising meta-substituted pyrene, possible calibrate sensor enhance both sensitivity chemical selectivity almost two orders magnitude so detected distinguished. These results provide strategy design high-performance graphene blocks.