New carbazole-based organic dyes with different acceptors for dye-sensitized solar cells: Synthesis, characterization, dssc fabrications and density functional theory studies

Carbazole dyes applied in dye-sensitized solar cells (DSSCs) are essential class of organic molecules. Two novel organic dyes DRA-BDC and DTB-BDC including rhodanine-3-acetic acid/thiobarbituric acid as electron acceptors and N, N-butyl dicarbazole structural as electron donor/spacer have been designed as photosensitizers for DSSCs. Both prepared dyes were characterized by IR, H-1 NMR, (13) C NMR, mass spectroscopy and CHN analysis. Results of photophysical properties, the UV- Visible spectra of both dyes DRA-BDC and DTB-BDC showed the higher absorption peaks at 440 and 370 nm, respectively. Also, for electrochemical properties, both structures showed more +ve ground state oxidation potential than I-/I (-3), and more -ve excited state oxidation potential than the conduction band edge of the semiconductor. However, the high performance of power-conversion was observed on the DSSCs device with DRA-BDC (eta= 1.16%) compared with DTB-BDC dye. Also, DRA-BDC recorded an open circuit voltage (V-OC) = 589 mV, short circuit current density (J(SC)) = 2.46 mA/cm(2) and fill factor (FF) = 0.79 under simulated AM 1.5 G irradiation (100 mW/cm(2)). For the theoretical studies included polarizabilities, optimization geometry, conformational analysis, and photovoltaic analysis based on frontier orbital analysis energy evaluated by using density functional theory model (DFT) with B3LYP/6-311functional basis set. (C)C 2020 Elsevier B.V. All rights reserved.

Automated summary

Carbazole dyes are crucial organic molecules used in dye-sensitized solar cells (DSSCs). Two novel organic dyes, DRA-BDC and DTB-BDC, designed with specific electron acceptors and donors, showed good photophysical and electrochemical properties for improved solar cell performance. The theoretical studies using density functional theory model provided additional insights on the molecular characteristics and potential applications in photovoltaics.