Molecular Modeling of Pentacyclic Aromatic Bislactam-Based Small Donor Molecules by Altering Auxiliary End-Capped Acceptors to Elevate the Photovoltaic Attributes of Organic Solar Cells

Abstract

Small-molecule (SM)-based organic solar cells (OSCs) have dominated the photovoltaic industry on account of their efficient optical and electronic properties. This quantum mechanical study addresses a DFT study of pentacyclic aromatic bislactam (PCL)-based small molecules for extremely proficient OSCs. Five novel small molecules ( PCLM1–PCLM5 ) retaining the A−π–A−π–D−π–A−π–A arrangement were fabricated from the reference PCLR . At the MPW1PW91/6-31G** level of theory, detailed profiling of these novel molecules was performed by accurately following DFT, along with the time-dependent density functional theory (TD-DFT) hypothetical simulations to analyze the UV–visible absorption (λ max ), light-harvesting efficiency (LHE), dipole moment (μ), fill factor (FF), open-circuit voltage ( V OC ), power conversion efficiency (PCE), frontier molecular orbitals (FMOs), binding energy ( E b ), density of states (DOS), electrostatic potential (ESP), and transition density matrix (TDM) plots. Alteration of peripheral acceptors in all of the molecular structures drastically modified their charge-transfer properties, such as a strong light-harvesting capability in the range of 0.9993–0.9998, reduced exciton E b (from 0.34 to 0.39 eV), a reduced bandgap ( E g ) in the range of 1.66–1.99 eV, an elevated λ max (775–959 nm) along with a higher μ in the solvent phase (1.934–7.865 D) when studied in comparison with PCLR , possessing an LHE of 0.9986, an E b of 0.40, an E g 2.27 eV, λ max at 662 nm, and a μ of 0.628 D. The FMO analysis revealed the uniform dispersal of charge density entirely along the highest occupied (HOMO) and lowest unoccupied (LUMO) molecular orbitals in newly constructed moieties. Electron as well as hole mobility rates, V OC , FF, and PCE of all novel molecules (PCLM1–PCLM5) were higher as compared with those of PCLR , ultimately making them exceptional candidates for solar devices. Focusing on the outcomes, terminal acceptor modification was found to be a suitable method for the development of highly tuned OSCs in the future.

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

“…TDM plots specify the charge density by different colors, ranging from dark blue at the end (zero electron density) to bright red at another extreme (high charge density) of the concerned molecule. The effect of all hydrogen atoms is not considered due to their small role in the transition of electrons . The studied molecules are divided into different parts according to the role and nature of every moiety present in that molecule.…”

“…The effect of all hydrogen atoms is not considered due to their small role in the transition of electrons. 93 The studied molecules are divided into different parts according to the role and nature of every moiety present in that molecule. The moieties were labeled as terminal acceptors ( A 2 ), the donor part (labeled as D ), and central acceptors ( A 1 ).…”

Quantum Modification of Indacenodithieno[3,2-b]thiophene-Based Non-fullerene Acceptor Molecules for Organic Solar Cells of High Efficiency

“…Examining the FMOs is crucial research because it reveals how effective molecules are in facilitating charge mobility and electron density dispersal . It helps us figure out how the charge is transmitted and facilitated across OSCs.…”

“…Examining the FMOs is crucial research because it reveals how effective molecules are in facilitating charge mobility and electron density dispersal. 36 It helps us figure out how the charge is transmitted and facilitated across OSCs. Molecules’ HOMO and LUMO energy profoundly affect their charge transfer, light absorption, and electrical properties.…”

Designing efficient materials for high-performance of non-fullerene organic solar cells through side-chain engineering on DBT-4F derivatives by non-fused-ring electron acceptors

“…In addition, solubility of the compounds is determined [58]. The spacing and charge flux of the donor and acceptor portions have a substantial impact on the opto-electronic efficacy of photovoltaic (PV) devices [59]. To speed up charge transferal within molecules, to promote crystallinity and self-assembly.…”