In this work, thin-film deposition of FePc particles nucleated and grown in gels was carried out in air by spin coating. The surface morphology and structure of these films were analysed by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. The optical parameters have been investigated using spectrophotometric measurements of transmittance in the wavelength range of 200–1100 nm. The absorption spectra recorded in the UV-Vis region for the deposited samples showed a single band, namely the B or Soret band in the region between 285 and 305 nm. The dependence of the Tauc and Cody optical gaps associated with the thickness of the film was determined and found to be around 4.2 eV from direct transitions and 3.8 eV from non-direct transitions. The films’ electric properties and their dependence in the presence of radiation of several wavelengths were evaluated. At lower voltages, ohmic conduction is evident, while space-charge limited conductivity (SCLC) governed by an exponential trap distribution is to be found at higher voltages.
Part of the book: Phthalocyanines and Some Current Applications