Computational design of poly( p ‐phenylene vinylene)‐based gas sensors: tunable reactivity and selectivity via side‐groupb functionalization

Poly( p ‐phenylene vinylene) (PPV) derivatives have emerged as promising materials for chemical sensor applications due to their favorable optoelectronic properties. Nevertheless, their intrinsic sensitivity and the nature of their interactions with analytes remain insufficiently understood. In this study, density functional theory (DFT) calculations were employed to evaluate the effects of side‐group functionalization on the molecular reactivity and electronic properties of PPV derivatives. Adsorption studies were also carried out using DFT and fully atomistic reactive molecular dynamics simulations, considering distinct gas‐phase analytes. The results reveal that the choice of substituent groups plays a critical role in shifting local reactivity toward the peripheral regions of the polymer chains, favoring effective electronic interactions with analytes. Notably, functionalization with electron‐withdrawing groups induced a significant modulation of the frontier molecular orbitals, shifting their energy levels by approximately 1.5 eV for PPV‐NO 2 and PPV‐CN relative to pristine PPV, and narrowing the bandgap by around 0.2 eV. Moreover, the adsorption studies provide quantitative insights into binding energies, which ranged from −0.14 eV for weak physisorption to −0.45 eV for the most stable complexes (such as PPV‐NO 2 /NH 3 ), clarifying how the analytes influence the electronic properties of the materials. Among the investigated derivatives, PPV‐CN and PPV‐NO 2 stand out for their effective interactions and significant optoelectronic responses, particularly in the presence of H 2 O, HCN and NH 3 . Our findings contribute to a deeper understanding of polymer–analyte interactions at the molecular level and support the rational design of new PPV‐based materials with improved performance for chemical sensing applications.