Porous silicon (PSi) non-symmetric multi-layers are modified by organic molecular beam deposition of an organic semiconductor, namely the N,N′-1H,1H-perfluorobutyldicyanoperylene-carboxydi-imide (PDIF-CN ₂ ). Joule evaporation of PDIF-CN ₂ into the PSi sponge-like matrix not only improves but also adds transducing skills, making this solid-state device a dual signal sensor for chemical monitoring. PDIF-CN ₂ modified PSi optical microcavities show an increase of about five orders of magnitude in electric current with respect to the same bare device. This feature can be used to sense volatile substances. PDIF-CN ₂ also improves chemical resistance of PSi against alkaline and acid corrosion.