Caracterização óptica de filmes finos de PEDOT:PSS/P3HT

Abstract

The main objective of this work is to study the interface between layers of thin films. This films were deposited on two types of substrate, in Indium Tin Oxide (ITO) and Fluorine Tin Oxide (FTO). Through the properties optics. Two sample sets were deposited on FTO and ITO. The first set a layer it was polymerspoly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT: PSS) deposited by Spin-Coa ting. PEDOT: PSS work as a passivating surface between the anode and the active layer in organic solar cells, for example, being a p-type semiconductor. And, on PEDOT:PSS it was deposited polymer another, poly 3-hexylthiophene (P3HT) which work for to of analyze the optical properties. P3HT has great potential for application in organic solar cells, the growth of the thin film was carried out by electrochemical synthesis, oxi dizing the monomer 3-hexylthiophene (3-HT), using the chronochoulometry technique. In the other sample set, it was deposited without PEDOT: PSS presence, for compari son. The films obtained were analyzed by ultraviolet-visible absorption (UV-Vis), cyclic voltammetry (VC), photoluminescence spectroscopy (PL), photoluminescent excitation spectroscopy (PLE), emission ellipsometry (EE) techniques. Through the UV-Vis spec tra it was possible to determine the optical gap that presented a higher value than that of the literature. The electronic gap, established with the cyclic voltammetry technique, assistance was satisfactory, consistent with that found by other groups. Photolumines cence spectra bands were wide and asymmetric, requiring studies through adjustments with some Gaussians, which made us suppose the existence of two distinct emission contributions in the formation of the spectra. These two contributions were attributed to the issuance of quinonic and pristine structure. Through the EE measures, it was found that the formed films showed polarization, being higher in the films that have PEDOT: PSS, reaching up to ∼ 37% for the film ITO: PEDOT: PSS / P3HT. From the results, obtained it was found that the use of PEDOT: PSS and the films produced in ITO resulted in an improvement in the properties in the development of an organic solar cell, such as increased polarization, for example.