Estudo das propriedades espectroscópicas de filmes poliméricos de poli-(3-hexiltiofeno) regiorregular dopados com moléculas de tetracianoquinodimetano

Abstract

In this work we have studied the optical properties of polymeric films of poly (3-hexylthiophene) (P3HT) with highly regio-regularity, doped with tetracyanoquinodimethane (TCNQ), as a function of concentration and temperature. The films were processed by casting deposition technique, with high degree of structural disorder and small homogeneity. In the characterization of these films, we have used the photoluminescence and ellipsometry emission techniques as function of temperature, as well as optical absorption. In the results of the absorption we observe the influence of TCNQ in P3HT, even in small doses. With the photoluminescence in function of temperature we analyzed the emission spectrum and we observed a blue shift jointly with loss of resolution of the peaks. Besides, in the photoluminescence we see the donwfall of the intensity of light emitted as a function of temperature, reflecting the increase of the vibrational intensity. From the results of ellipsometry emission we obtained the Stokes parameters. Through these parameters we find the predominance in type of polarization, the degree of polarization and molecular anisotropy.