High-Efficiency and Low-Energy-Loss Organic Solar Cells Enabled by Tuning the End Group Modification of the Terthiophene-Based Acceptor Molecules to Enhance Photovoltaic Properties

Abstract

In the current study, six nonfullerene small acceptor molecules were designed by end-group modification of terminal acceptors. Density functional theory calculations of all designed molecules were performed, and optoelectronic properties were computed by employing different functionals. Every constructed molecule has a significant bathochromic shift in the maximum absorption value (λ max ) except AM6. AM1−AM4 molecules represented a narrow band gap (E g ) and low excitation energy values. The AM1−AM4 and AM6 molecules have higher electron mobility. Comparing AM2 to the reference molecule reveals that AM2 has higher hole mobilities. Compared to the reference molecule, all compounds have excellent light harvesting efficiency values compared to AM1 and AM2. The natural transition orbital investigation showed that AM5 and AM6 had significant electronic transitions. The open-circuit voltage (V oc ) values of the computed molecules were calculated by combining the designed acceptor molecules with PTB7-Th. In light of the findings, it is concluded that the designed molecules can be further developed for organic solar cells (OSCs) with superior photovoltaic abilities.

Engineering of the Central Core on DBD-Based Materials with Improved Power-Conversion Efficiency by Using the DFT Approach

“…LHE is significantly related to oscillator strength, ultimately affecting the production of short-circuit current ( J sc ). Thus, the efficiency of solar devices is highly influenced by their ability to harvest sunlight. , Equation was used to calculate the LHE of all currently studied molecules LHE = 1 − 10 − f where “ f ” corresponds to the oscillator strength in the solvent phase of molecules.…”

Designing Thieno[3,4-c]pyrrole-4,6-dione Core-Based, A2–D–A1–D–A2-Type Acceptor Molecules for Promising Photovoltaic Parameters in Organic Photovoltaic Cells

“…We can comprehend the type and strength of molecular interaction by inspecting the electron density amount of the RDG versus sign (λ 2 )ρ peaks. 81 Repulsion (nonbonded) and attraction (bonded) interaction can be denoted as the λ 2 > 0 and λ 2 < 0 signs. These interactions are visualized by VMD and Multiwfn software.…”

Theoretical investigation of substituted end groups in thiophene‐phenyl‐thiophene (TPT) derivatives for high efficiency organic solar cells

“…This indicates that most of our molecules have a low value of band gap compared to R. TP6 showed highest band gap, which is attributed to its high-lying LUMO level, as it is energetically unfavorable to add electrons in it. 61 The least band gap exhibited by TP8 is due to the insertion of thiazol ring making the acceptor a powerful withdrawer, which has attracted almost all the charge density towards itself. The presence of thiophene rings in the end acceptors is responsible for the second-lowest band gap value observed in TP9.…”