Optical absorption and dispersion analysis of nanocrystalline perylene-3,4,9,10-tetracarboxylic-3,4,9,10-dianhydride film prepared by dip coating and its optoelectronic application

High uniform and good adhesion of nanocrystalline films of perylene-3,4,9,10-tetracarboxylic-3,4,9, 10-dianhydride (PTCDA) were successfully deposited by dip coating technique. The surface morphology characteristic of the film was studied by scanning electron microscopy (SEM). The X-ray diffraction patterns of PTCDA film is characterized by a single wide peak along (102) orientation. The absorption spectrum of the film shows an intense band in the UV region followed by Q-band in the visible region. The onset optical and transport energy gaps were found to be 1.76 and 3.16 eV, respectively. The dispersion parameters and the ratio of free carrier concentration to the effective mass were also estimated. The photovoltaic characteristics of the device based PTCDA under illumination of 100 mW/cm(2) were also considered. (C) 2012 Elsevier Ltd. All rights reserved.