Search

[Display omitted] • Nine anthradithiophene-based photovoltaic compounds are designed for bulk heterojunction solar cells. • The optoelectronic properties were studied in detail using DFT and TDDFT calculations. • The FMO, MEP, UV–Visible, DOS, TDM, and Voc, and are performed. • All investigated molecules exhibit remarkable optoelectronic properties. • Investigated molecules are recommended for future solar cell applications. The optoelectronic characteristics of fullerene-free photovoltaic compounds hold significant value in photonics and optoelectronics applications. To obtain the optimal candidate for modernized hi-tech purposes and to meet the rising requirement of photovoltaic blends for future solar cell applications, the current study centered on simulating and conducting DFT-analysis-of-synthesized anthradithiophene-based reference (RS) and nine tailored molecules (ZHS1–ZHS9). DFT and time-dependent-DFT methods were utilized to determine the photochemical, optoelectronic, and photovoltaic parameters such as absorption behavior, energy gaps, charge transfer capabilities, TDM analysis, reorganizational energy, charge transfer complex ZHS5:PC 61 BM study for ZHS1–ZHS9 and RS. The absorption maxima of ZHS1–ZHS9 molecules resulted in red shifting (680–816 nm) compared to the synthesized RS reference molecule (454 nm). The distribution of electron density on various molecular components is confirmed by the DOS and FMOs analysis. All tailored molecule possesses less energy gap, while ZHS5 gave the narrowest bandgap (1.21 eV) with less binding energy (0.19 eV) as well as excitation energy (1.02 eV) as compared to the reference molecule. The developed molecules carried larger open-circuit voltage (Voc = 1.04–1.88 V) and fill factor (FF=0.93) than the reference molecule Voc = 0.47 V and FF=0.803594, indicating that they are better suited to drawing more electric current. The ZHS5:PC 61 BM blend study and overall outcomes showed that these planned donor molecules are photo and thermally stable efficient solar cell candidates, and their ongoing research has the potential to result in high-performance photovoltaic systems. Thus, this work encouraged experimenters to create the suggested solar cell materials for cutting-edge optoelectronic high-tech uses. [ABSTRACT FROM AUTHOR]

AbstractDye-sensitized solar cells (DSSCs) have garnered significant attention due to their exceptional ability to convert solar energy into electricity at a relatively low cost. Novel organic photosensitizers (FZB1-FZB9) from the pyrazine-based aromatic dye (E)-3-(5-(2,3-bis(40-(diphenylamino)-[1,10-biphenyl]-4-yl)-7 (trifluoromethyl)quinoxalin-5-yl)thiophen-2-yl)-2-cyanoacrylic acid (TPPF) have been quantum chemically modeled for their application in dye-sensitized nanocrystalline TiO2 solar cells (DSSCs). The electrochemical and photovoltaic features of modeled dyes are investigated by performing DFT insights, i.e. FMOs, absorption maxima, DOS, TDM, NBO, exciton and binding energy, radiative lifetime analysis (ꚍ), electron-injection (ΔGinject) and regeneration analysis (ΔGdyeregen)@TiO2. FMO analysis confirmed the better electron injection as HOMO of designed dyes was found to be more positive than redox potential I/I3 (-4.8 eV), and the LUMO appeared more negative than the conduction band of TiO2 (-4.0 eV). The modeled photosensitizers exhibited red shift λmax from 338-494 nm with a lower energy gap from 5.62 eV in FZB (R) to 5.17 eV in FZB9. Bridging modification reduces the exciton and binding energy for designed dye FZB9 and FZB7 compared to reference FZB. The designed dyes appeared with a lower radiative lifetime of up to 1.32 than the reference dye of 1.63, better light harvesting efficiency (LHE), and the highest NBO charge on bridges of designed photosensitizers for enhanced light emitting efficiency. The investigated dyes exhibited more negative values for electron injection, i.e. −0.003 and the highest values of dye regeneration (ΔGregedyeregen) up to 11.717, which unveils innovative and effective injection of electrons toward semiconductor TiO2. Among all dyes, FZB8 proved best with the novel bridging modification that enables quick charge transfer as exhibited the lowest gap (5.17 eV), lowest excitation energy, better LHE, highest charge on LUMO and more negative electron injection (ΔGinject). The outcomes of this computational study confirmed that this research established a new benchmark for achieving novel and efficient photosensitizers, thus recommending them for future DSSC applications. [ABSTRACT FROM AUTHOR]

Hole transport materials (HTMs), especially dopant-free hole transport materials, are getting attention in enhancing the power conversion efficiencies and stabilities of organic solar cells (OSCs). Herein, we have designed efficient dopant-free HTMs (DM1–DM5) from an outstanding synthetic DFM molecule (having 20.6% PCE). Photo-physical, photovoltaic, optoelectronic and structural-property relationship of newly designed molecules are extensively studied and compared with DFM (R). Density functional theory (DFT) and time-dependent-density functional theory (TD-DFT) have been employed to investigate the alignment of frontier molecular orbitals (FMOs), optical properties, density of states along with transition density matrix, binding and excitation energy, reorganizational energies and for open-circuit voltages of all newly designed molecules. Red-shifting in absorption spectrum offers high power conversion efficiencies, and our tailored molecules exhibit red-shifting in absorption spectrum (λmax = 391–429 nm) as compared to R (λmax = 396 nm). In addition, our all designed molecules expressed better hole transport ability (λh = 0.0056–0.0089 eV) as compared to R (λh = 0.0101 eV). Similarly, DM1–DM5 disclosed narrow HOMO–LUMO energy gap which causes maximum charge transfer from excited HOMO to excited LUMO. The theoretical study of DM3/PC61BM and DM3/Y6 complexes is also performed in order to understand the shifting of charge between donor and acceptor molecules. Results of all analysis clearly show the efficient designing of dopant-free (DM1–DM5) molecules and their possible potential to fabricate a high performance and stable organic solar cells devices. Therefore, the theoretical proposed molecules are recommended to experimentalists for future highly efficient organic solar cells. [ABSTRACT FROM AUTHOR]