Comparison of interaction mechanisms of lead phthalocyanine and disodium phthalocyanine with functionalized 1,4 dihydropyridine for optoelectronic applications

Abstract 
In the current work, the compound 2-methyl-N-octadecyl-2-(1-((trifluoromethyl)sulfonyl)-1,4-dihydropyridin-4-yl) propanamide was synthesized and characterized. Subsequently, its structure was optimized by DFT (Density Functional Theory) and its interaction with the chosen phthalocyanines: lead phthalocyanine (PbPc) and disodium phthalocyanine (Na2Pc) were also theoretically studied. The energy values of the HOMO (Highest Occupied Molecular Orbital) and the LUMO (Lowest Unoccupied Molecular Orbital), as well as the band gap were obtained from the resulting complex and a semiconductor behavior was found. Based on the theoretical results, bulk heterojunction films were manufactured with the aim of using them as semiconductor active layers in optoelectronic devices. In those films, the bandgap was determined through their absorption coefficients and the energy values of the photon, the results were compared to the theoretical bandgap previously calculated. Finally, the electrical behavior of the electronic donor-acceptor active layers was evaluated in form of simple devices with a heterojunction arrangement. The evaluation of the current-voltage (I–V) was carried out under the presence of different lighting conditions and the devices showed the curve of a typical semiconductor. No variations between the forward and reverse operation zones were shown by the devices, not even when they were exposed to different illumination sources. In general, an ohmic behavior was observed. Results demonstrated that 2-methyl-N-octadecyl-2-(1-((trifluoromethyl)sulfonyl)-1,4-dihydropyridin-4-yl) propenamide can be used as an electron acceptor species for the manufacture of semiconductor active layers of optoelectronic devices.