Synthesis, characterization and exploration of photovoltaic behavior of hydrazide based scaffolds: a concise experimental and DFT study

Solar energy being a non-depleting energy resource, has attracted scientists' attention to develop efficient solar cells to meet energy demands. Herein, a series of hydrazinylthiazole-4-carbohydrazide organic photovoltaic compounds (BDTC1-BDTC7) with an A1-D1-A2-D2 framework was synthesized with 48-62% yields, and their spectroscopic characterization was accomplished using FT-IR, HRMS, H-1 and C-13-NMR techniques. Density functional theory (DFT) and time dependent DFT analyses were performed utilizing the M06/6-31G(d,p) functional to calculate the photovoltaic and optoelectronic properties of BDTC1-BDTC7via numerous simulations of the frontier molecular orbitals (FMOs), transition density matrix (TDM), open circuit voltage (V-oc) and density of states (DOS). Moreover, the conducted analysis on the FMOs revealed efficient transference of charge from the highest occupied to the lowest unoccupied molecular orbitals (HOMO & RARR; LUMO), further supported by TDM and DOS analyses. Furthermore, the values of binding energy (E-b = 0.295 to 1.150 eV), as well as reorganization energy of the holes (-0.038-0.025 eV) and electrons (-0.023-0.00 eV), were found to be smaller for all the studied compounds, which suggests a higher exciton dissociation rate with greater hole mobility in BDTC1-BDTC7. V-oc analysis was accomplished with respect to HOMOPBDB-T-LUMOACCEPTOR. Among all the synthesized molecules, BDTC7 was found to have a reduced band gap (3.583 eV), with a bathochromic shift and absorption maximum at 448.990 nm, and a promising V-oc (1.97 V), thus it is regarded as a potential candidate for high performance photovoltaic applications.