Abstract
Thin films of 2,9-Bis [2-(4-chlorophenyl)ethyl] anthrax [2,1,9-def:6,5,10-d'e'f'] diisoquinoline-1,3,8,10 (2H, 9H) tetrone (Ch-diisoQ) were prepared by the well-known thermal evaporation technique. The molecular structure of Ch-diisoQ in its powder form as well as the as-deposited and annealed Ch-diisoQ thin films was identified by Infrared (IR) spectroscopy. The analysis of X-ray diffraction of Ch-diisoQ thin films showed that this organic material is realized by its nanostructure nature and the crystal size was increased by increasing the annealing temperature. The dark electrical conductivity of Ch-diisoQ was studied at different temperatures in the range of 298–423 K for as-deposited and annealed films. The calculated values of activation energy were found to be decreased as the annealed temperature increased. The current density-voltage (J-V) characteristics of Ch-diisoQ films were studied at different temperatures. The obtained results from the slope of J-V plot indicated that the conduction mechanism was Ohmic in a low voltage range. While in the high-voltage range, the conduction mechanism was observed to be space charge limited conductivity (SCLC) demonstrated by a single dominating trap level. From the experimental calculations, the values of Fermi level position (EF) and the mobility of electrons (μ) were found to be 0.231 eV and 1.56 × 10−10 cm2V−1s−1, respectively. Whereas, the concentration of traps (Nt) at the energy level (Et) below the conduction band edge was evaluated as 3.35 × 1014 cm−3. The proper values of EF, μ and Nt of Ch-diisoQ films suggests strongly the utilizing of this manufactured thin films for their use in desired heterojunction solar cell.
•Films of Ch-diisoQ as n-type organic of were deposited by an evaporation technique.•The crystal size of Ch-diisoQ films was increased by annealing temperature.•The current density-voltage characteristics of Ch-diisoQ films were studied.•In high-voltage range, space charge limited conductivity (SCLC) was observed.•The obtained mobility of electrons suggests Ch-diisoQ as solar cell material.