How Does Bridging Core Modification Alter the Photovoltaic Characteristics of Triphenylamine‐Based Hole Transport Materials? Theoretical Understanding and Prediction

Abstract

Perovskite solar cells have gained immense interest from researchers owing to their good photophysical properties, low-costp roduction,a nd high powerc onversion efficiencies. Hole transport materials (HTMs) play ad ominant role in enhancing the powerc onversion efficiencies (PCEs) and long diffusion length of holes and electrons in perovskite solar cells. In hole transportm aterials, modification of p-linkers has proved to be an efficient approach fore nhancing the overall PCE of perovskite solar cells. In this work, plinker modification of ar ecently synthesized HÀBi molecule (R)i sa chieved with novel p-linkers. After structural modifications, ten novel HTMs (HB1-HB10)w ith aD ÀpÀDb ackbone are obtained. The structure-propertyr elationship, ando ptoelectronic and photovoltaic characteristics of thesen ewly designed hole transport materials are examined comprehensively and compared with reference molecules. In addition, different geometric parameters are also examined with the assistance of density functional theory (DFT) and time-dependent DFT.A ll the designed molecules exhibit narrow HOMO-LUMO energy gaps (E g = 2.82-2.99 eV) compared with the R molecule (E g = 3.05 eV). The designed molecules express redshifting in their absorption spectra with low valueso fe xcitation energy, which in return offer high power conversion efficiencies. Further, density of states and molecular electrostatic potential analysis is performed to locate the differentc harge sites in the molecules. The reorganizational energies of holes and electrons are found to have good values, suggesting that thesen ovel designed molecules are efficient hole transport materials for perovskite solar cells. In addition, the low binding energy values of the designed molecules (compared with R)o ffer high current charged ensity.F inally,c omplex study of HB9:PC 61 BM is also undertaken to understand the charget ransfer between the molecules of the complex.T he resultso fa ll analyses advocate that these novel designed HTMs are promising candidates for the constructiono ffuture high-performance perovskite solarcells.

Quantum Chemical Design of D–π–A‐Type Donor Materials for Highly Efficient, Photostable, and Vacuum‐Processed Organic Solar Cells

“…The lowest unoccupied and highest occupied-MOs energies along with bandgap of all the molecules (R, ZDM1-ZDM5) are determined at the DFT/ MPW1PW91 theory and results are shown in Table 1, whereas the optimized geometries of all the theoretically planned molecules are shown in Figure 3 Energy gap (E g ) is the main factor in solar cell conduction, because it gives significant data for charge transfer. [45][46][47] R has the highest energy gap (E g ¼ 2.04 eV) value among ZDM1-ZDM5. In comparison with R, the energy gap in ZDM1 molecules reduces to 1.93 eV which represents the effect of methoxy (end-capped atoms) in ZDM1.…”

Computational engineering to enhance the photovoltaic by end‐capped and bridging core alterations: Empowering the future with solar energy through synergistic effect in D‐A materials

“…Distribution of FMOs also computed in order to unveil the position of both MOs on theoretically designed molecules as explained in literature as well [34, 36]. The distribution pattern of MOs of our studied molecules is shown in Figure 5.…”

Exploration of Nonlinear Optical Properties for the First Theoretical Framework of Non-Fullerene DTS(FBTTh2)2-Based Derivatives

“…The study of frontier molecular orbitals (FMOs) is extremely significant for an understanding of the optical and electric characteristics of species, and it is also utilized to investigate their chemical stability. 44 − 46 The highest occupied molecular orbitals are referred to as HOMOs, while the lowest unoccupied molecular orbitals are referred to as LUMOs, which are very significant FMOs. 47 − 52 An FMO analysis enables us to determine significant quantum chemistry parameters, including electronic properties, chemical stabilities, electron transfer properties, and reactivities, of the investigated compounds.…”