Structural characterization and optical investigation of (E)-2-((9, 10-dioxo-9,10- dihydroanthracen-2-yl) amino)-2-oxo-N′-(p-tolyl) acetohydrazonoyl cyanide films for photosensor applications

Abstract

A thin film of (E) − 2-((9, 10-dioxo-9,10-dihydroanthracen-2-yl) amino) − 2-oxo-N′-(p- tolyl) acetohydrazonoyl cyanide, CDATA, was prepared as a new class of organic thin films for photosensor applications. Thermal evaporation under high vacuum was used to produce premium quality CDATA films, which were extensively characterized using various analyzer techniques like x-ray diffraction (XRD), scanning electron microscopy(SEM), and Fourier-transform infrared spectroscopy (FTIR). For the first time, the Miller indices for preferred orientations of CDATA were calculated using a specific program. Using the Williamson–Hall plots, the average crystal size and lattice strain were determined to be 20.5 nm and 4 × 10−3, respectively. Both a direct bandgap of 2.65 eV and an indirect bandgap of 1.95 eV are present in thin films of CDATA. The absorption tail was examined, and the Urbach energy was found to be 320 meV. The dispersion, oscillator energies, and high-frequency dielectric constants were found to be 12.07 eV, 3.76 eV, and 4.35 eV, respectively, in the non-absorbing region. In the dark and under various illuminations ranging from 30 mW/cm2 to 80 mW/cm2, the heterojunctions of Au/CDATA/p- Si/In show a suitable rectifying feature. The presence of a continuous trapping center distribution is indicated by the studied heterojunction. According to the determined characteristic parameters, the Au/CDATA/p-Si/In heterojunction could be useful in optoelectronic device applications.