Study on Photo-physical Properties of News Synthesized Olygophenylene Derivatives

In this chapter, photophysical properties of newly synthesized oligophenylene derivatives are studied through ultraviolet-visible (UV-vis), steady-state, and time-resolved photoluminescence spectroscopies. The investigated oligophenylene derivatives are obtained by Knoevenagel condensation of the synthesized oligo[4-(methoxyphenyl) acetonitrile] (OMPA) with various chemical groups. Under the chemical modifications, significant changes in the photo-physical properties were observed. Indeed, the chemical insertion of the dimethyl-amine group on the backbone of the OMPA oligomer induces a decrease in the optical band gap and a red-shift of the absorption and photoluminescence properties, which is a signature of an intermolecular charge transfer that occurred under the chemical modification. Meanwhile, the chemical insertion of aromatic chemical groups (anthracene and thiophene) permitting to improve the luminescence properties of the synthesized oligophenylene. The chemical insertion of the focused chemical groups induces a change in the thermal properties.