Structural and Optical Properties of Nanocrystalline 3,4,9,10-Perylene-Tetracarboxylic-Diimide Thin Film

Abstract

Thin films of nanocrystalline 3,4,9,10-perylene-tetracarboxylic-diimide (PTCDI) were prepared on quartz substrates by thermal evaporation technique. The structural properties were identified by transmission electron microscopy (TEM) and the X-ray diffraction (XRD). The optical properties for the films were investigated using spectrophotometric measurements of the transmittance and reflectance at normal incidence of light in the wavelength range from 200 to 2500 nm. The optical constants (refractive indexnand absorption indexk) were calculated and found to be independent on the film thickness in the measured film thickness range 117–163 nm. The dispersion energy (Ed), the oscillator energy (Eo), and the high-frequency dielectric constantε∞were obtained. The energy band model was applied, and the types of the optical transitions responsible for optical absorption were found to be indirect allowed transition. The onset and optical energy gaps were calculated, and the obtained results were also discussed.

Calculating Optical Absorption Spectra of Thin Polycrystalline Organic Films: Structural Disorder and Site-Dependent van der Waals Interaction

“…For a thin polycrystalline PTCDI film, a refractive index n PTCDI = 1.96 is reported. 16 , 17 Application of CSA predicts a rather substantial level shift of meV with respect to E gp which is in the range of the observed spectral changes (cf. Figure 1 ).…”

Surface doping in T6/PDI-8CN2 heterostructures investigated by transport and photoemission measurements

“…of a 4-5 nm layer of T6 over the whole metal surface, also among islands, thus avoiding any significant PDI-8CN 2 /Au interaction also through tunnelling processes [4]. On the other hand, the T6 HOMO BE shift is an evidence of the organic involvement in the charge transfer process [3,4,17,21] and is a further indication that the increase in the source drain current in the output and transfer curves is completely due to a surface doping of T6 by PDI- respectively [22,28]. The proposed level alignment at the heterojunction is in agreement with other studied organic systems [2,[29][30][31] and confirms results for the PDI-8CN 2 /T6 bilayers (with different thicknesses) achieved by some of the authors of this study, where a substantial charge transfer process was supposed between the two organics [10].…”

Sensing and surface morphological properties of a poly[(9,9‐dioctylfluorenyl‐2,7‐diyl)‐co‐bithiophene] liquid‐crystalline polymer for optoelectronic applications

“…As shown in Table , the E d value (4.196 eV) of the F8T2 polymer for 1.200 μ M was lower than the E d value (6.692 eV) of the F8T2 polymer at 2.290 μ M, whereas the E 0 value (2.147 eV) of the F8T2 polymer at 1.200 μ M was higher than the E 0 value (2.135 eV) of the F8T2 polymer at 2.290 μ M . The E d values (4.196 and 6.692 eV) of the F8T2 polymer were lower than the E d value (14.532 eV) of the CoPc thin film, the E d value (10.0 eV) of the Y 0.225 Sr 0.775 CoO 3±δ thin film, and the E d value (6.59 eV) of the 3,4,9,10‐perylene‐tetracarboxylic‐diimide (PTCDI) thin film, whereas the E d value (6.692 eV) of the F8T2 polymer was higher than the E d value (6.017 eV) of another PTCDI thin film . The E 0 values (2.147 and 2.135 eV) of the F8T2 polymer were lower than the E 0 value (2.41 eV) of the first PTCDI thin film, the E 0 value (2.909 eV) of the second PTCDI thin film, the E 0 value (3.76 eV) of the Y 0.225 Sr 0.775 CoO 3±δ thin film, and the E 0 value (5.5 eV) of the CoPc thin film reported in the literature.…”

“…The surface roughness parameters of semiconductor films affect the performances of sensor design, biological imaging, light‐emitting devices, and detection . The surface morphological properties of the materials can affect the luminescence and charge‐transport properties …”