Novel A-π-D-π-A type non-fullerene acceptors of dithienyl diketopyrropopyrrole derivatives to enhance organic photovoltaic applications: a DFT study

Abstract

The investigated non-fullerene acceptor molecules TM1, TM2, TM3, TM4, TM5, TM6, and TM7 that are fashioned by making alterations at the terminal position of reference molecule TMR demonstrate significant absorption in the visible region.

Effect of Benzothiadiazole-Based π-Spacers on Fine-Tuning of Optoelectronic Properties of Oligothiophene-Core Donor Materials for Efficient Organic Solar Cells: A DFT Study

“…The excitation energy ( E ex ) is a key factor in predicting the efficiency of the donor material in OSCs, where E ex defines the energy required for an electron to be excited from S 0 to S 1 . A lower E ex is beneficial, leading to easier electronic excitation and smoother charge migration . This increased ability of molecules D1–D5 to efficiently transport electrons in comparison to R is illustrated in Figure b by a significant decrease of E ex .…”

“…A lower E ex is beneficial, leading to easier electronic excitation and smoother charge migration. 63 This increased ability of molecules D1−D5 to efficiently transport electrons in comparison to R is illustrated in Figure by a significant decrease of E ex . The excitation energies are larger than the corresponding gap energies because the HOMO → LUMO transition contribution to the main absorption peak is on the order of 50% with additional contributions from weaker transitions from different energy levels.…”

Exploring the Electronic, Optical, and Charge Transfer Properties of A-D-A-Type IDTV-ThIC-Based Molecules To Enhance Photovoltaic Performance of Organic Solar Cells

“…Four distinct functionals, i.e., B3LYP, CAM-B3LYP, MPW1PW91, and ωB97XD were employed for the inspection of the optical behavior of reference ( IDTV-ThIC ) molecule at the 6-31G­(d,p) basis set of density functional theory. Among these density functionals, the MPW1PW91 was opted for further analysis of molecules due to the closeness of results of MPW1PW91 functional with experimental results. − As cited in the literature, the experimentally obtained λ max of IDTV-ThIC lies at 669 nm . While the theoretically acquired λ max of IDTV-ThIC appeared at 728, 523, 676 , and 486 nm for B3LYP , CAM-B3LYP , MPW1PW91 , and ωB97XD functionals, respectively.…”

Theoretical Insights into the Effect of Conjugated Cores on Optical and Photovoltaic Properties of Small Molecule Acceptors for Organic Solar Cells

“…[18] The electronic band gap is the difference between the vertical ionization energy and the vertical electron affinity energy, and the optical gap is the lowest excitation energy. [37] Generally, the smaller the E b , the easier of exciton dissociation into free charge, resulting in the decrease of E loss , thus increasing V oc of OSCs. As shown in Figure 3 The reorganization energy (λ) between neutral and anionic states is one of the key factors determining the electron transfer rate.…”