Optoelectronic properties of acceptor fine-tuning via benzothiadiazole efficient D-A-A-based materials for solar cells with non-linear optical activity by TD-DFT method

Here, attempts have been made to create and investigate acceptor tuning (A) materials via benzothiadiazole (BDT) that have higher efficiency for photovoltaic (PV). By structurally altering the BDT A-moiety of 2-((7-(N-(isobutyl)-benzothieno[3,2-b]-thieno[2,3-d]-pyrrol-2-yl)benzo[c][1], [2], [5]thiadiazol-4-yl)-methylene)malononitrile (iBuBTDC), three organic compoundsA1-A3 were designated for organic solar cells (OSCs) using the time-dependent density functional theory (TD-DFT) techniques. All A1-A3 molecules (1.85–1.93 eV) show a smaller energy gap (Eg) and exhibit the best outcomes for the open circuit voltage (VOC) (1.04–1.18 eV), normalized VOC (41.154 to 46.559 V) and FF (0.885 to 0.896 a.u.). The λ- and λ+ values of all compounds (0.1959, 0.1850, 0.1932 and 0.1877, 0.1659, 0.1641 eV) are found to be lower than the iBuBTDC (0.2122 and 0.1945 eV). Thefirst-order hyperpolarizability (β) and polarizability (α) were used to compute the Non-Linear Optical (NLO) characteristics of the A1-A3 molecules. Especially A3 could be very useful for future experimentally designed OSCs along with NLO applications.