Experimental and first-principles study of a new hydrazine derivative for DSSC applications

Hydrazine derivatives have a wide variety of applications in organic synthesis, material science, medical treatments, as well as the dye-sensitized solar cells (DSSC). In this work, the molecular structure, electronic spectra and first principles investigation for the exo-endo isomerization in (1E,2E)-bis[1-(4-nitrophenyl)ethylidene]hydrazine were studied. The structural interactions and synthon formations have been determined experimentally via Hirshfeld surface analysis (HSA) and two-dimensional fingerprint plots (2D-FP). Furthermore, the solid-state XRD/HSA interactions have been used to explain the physical behavior of the compound. The transition state for the exo-endo isomerization was located using density functional theory (DFT). The activation barrier is estimated to be 110.5 kJ/mol (in vacuo). The endo isomer was found to be slightly more stable than the exo one. The UV-Vis spectra of the two isomers were obtained using time-dependent density functional theory (TDDFT) and compared to the experimental spectra in vacuo, water, and methanol. To explore the potential of the new compound as a DSSC sensitizer, the emission spectrum was also constructed by optimizing the singlet electronic excited state. (C) 2020 The Author(s). Published by Elsevier B.V.

Automated summary

In this study, the molecular structure, electronic spectra, and exo-endo isomerization of (1E,2E)-bis[1-(4-nitrophenyl)ethylidene]hydrazine were investigated using experimental and theoretical methods. The interactions and synthon formations of the compound were determined, and the potential applications in DSSC were explored through UV-Vis and emission spectra analysis. The endo isomer was found to be slightly more stable than the exo one, with an estimated activation barrier of 110.5 kJ/mol.