Sarin-simulant detection by phthalocyanine/palladium structures: From modeling to real sensor response

•The new approach to comprehensive sensing mechanism description presented.•The study of DMMP adsorption on H2Pc/Pd/PdO structures at room temperature.•The investigation consisted of semi-empirical modeling and experimental part.•The existence of PdO considered in modeling and confirmed in experiment.•Main sensing mechanism – physisorption through dipolar layer of adsorbate.