Insights into end‐capped modifications effect on the photovoltaic and optoelectronic properties of S‐shaped fullerene‐free acceptor molecules: A density functional theory computational study for organic solar cells

AbstractConsidering the increased demand and potential of photovoltaic devices in clean, renewable electrical and hi-tech applications, non-fullerene acceptor (NFA) chromophores have gained significant attention. Herein, six novel NFA molecules IBRD1–IBRD6 have been designed by structural modification of the terminal moieties from experimentally synthesized A2-A1-D-A1-A2 architecture IBR for better integration in organic solar cells (OSCs). To exploit the electronic, photophysical and photovoltaic behavior, density functional theory/time dependent-density functional theory (DFT/TD-DFT) computations were performed at M06/6-311G(d,p) functional. The geometry, electrical and optical properties of the designed acceptor molecules were compared with reported IBR architecture. Interestingly, a reduction in bandgap (2.528–2.126 eV), with a broader absorption spectrum, was studied in IBR derivatives (2.734 eV). Additionally, frontier molecular orbital findings revealed an excellent transfer of charge from donor to terminal acceptors and the central indenoindene-core was considered responsible for the charge transfer. Among all the chromophores, IBRD3 manifested the lowest energy gap (2.126 eV) with higher λmax at 734 and 745 nm in gaseous phase and solvent (chloroform), respectively due to the strong electron-withdrawing effect of five end-capped cyano groups present on the terminal acceptor. The transition density matrix map revealed an excellent charge transfer from donor to terminal acceptors. Further, to investigate the charge transfer and open-circuit voltage (Voc), PBDBT donor polymer was blended with acceptor chromophores, and a significant Voc (0.696–1.854 V) was observed. Intriguingly, all compounds exhibited lower reorganization and binding energy with a higher exciton dissociation in an excited state. This investigation indicates that these designed chromophores can serve as excellent electron acceptor molecules in organic solar cells (OSCs) that make them attractive candidates for the development of scalable and inexpensive optoelectronic devices.

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Tuning of optoelectronic properties of triphenylamines-based donor materials for organic solar cells

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633619500366 ◽

2019 ◽

Vol 18 (07) ◽

pp. 1950036

Author(s):

Maria Naeem ◽

Sobia Jabeen ◽

Rasheed Ahmad Khera ◽

Usama Mubashar ◽

Javed Iqbal

Keyword(s):

Solar Cells ◽

Acrylic Acid ◽

Organic Solar Cells ◽

Density Functional ◽

Acid Methyl Ester ◽

Reorganization Energy ◽

Optoelectronic Properties ◽

Functional Theory ◽

Acid Methyl ◽

Donor Moiety

In the present study, four molecules have been designed by substituting various acceptor moieties around the triphenylamine donor moiety like 2-cyano acrylic acid (R), 2-methylene malonitrile (M1), 2-cyano acrylic acid methyl ester(M2), 2-(2-methylene-3-oxo-indan-1-ylidene)-malonitrile (M3), 2-(6,7-difluoro-2-methylene-3-oxo-indan-1-ylidene)-malonitrile (M4), respectively. CAM-B3LYP/6-31G (d, p) level of theory by using density functional theory (DFT) has been used for the investigation of optoelectronic properties of four new triphenylamine (TPA)-based donor materials (M1–M4) for organic solar cells. In comparison with the recently reported reference molecule, the optoelectronic properties of designed molecules were evaluated. M4 showed absorption maxima at 520[Formula: see text]nm due to extended conjugation with bridged thiophene group. Results of reorganization energy calculations also favor M4 exhibiting highest transfer rate of hole as depicted from its low reorganization energy of hole ([Formula: see text].

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Design and characteration of planar star-shaped oligomer electron donors for organic solar cells: a DFT study

Canadian Journal of Chemistry ◽

10.1139/cjc-2015-0096 ◽

2015 ◽

Vol 93 (11) ◽

pp. 1181-1190 ◽

Cited By ~ 1

Author(s):

Dongmei Wang ◽

Zhiyuan Geng

Keyword(s):

Density Functional Theory ◽

Solar Cells ◽

Charge Transfer ◽

Energy Level ◽

Organic Solar Cells ◽

Density Functional ◽

Short Circuit ◽

Frontier Molecular Orbital ◽

Orbital Energy ◽

Functional Theory

To seek high-performance oligomer donor materials used in organic solar cells, four star-shaped molecules with a planar donor core derived from the recent reported molecule 3T-P-DPP (phenyl-1,3,5-trithienyl-diketopyrrolopyrrole) were designed. The molecular properties affecting the cell performance, such as structural characteristics, frontier molecular orbital energy level, absorption spectra, exciton character, and charge transfer/transport, were investigated by means of the density functional theory and time-dependent density functional theory methods. Comparative analysis showed that the new designed molecule 3 with a TTT (2,4,6-tri(thiophen-2-yl)-1,3,5-triazine) core has better planarity, a lower HOMO energy level, and a higher absorption efficiency, as well as more favorable exciton dissociation and charge transfer than the others, potentially improving the open-circuit voltage and short-circuit current density. Consequently, 3 maybe superior to 3T-P-DPP and may act as a promising donor material candidate for organic solar cells.

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Time-Dependent Density Functional Theory Study on Cyclopentadithiophene-Benzothiadiazole-Based Push-Pull-Type Copolymers for New Design of Donor Materials in Bulk Heterojunction Organic Solar Cells

Bulletin of the Korean Chemical Society ◽

10.5012/bkcs.2012.33.3.1029 ◽

2012 ◽

Vol 33 (3) ◽

pp. 1029-1036 ◽

Cited By ~ 11

Author(s):

Ja-Min Ku ◽

Dae-Kyun Kim ◽

Taek-Hee Ryu ◽

Eun-Hwan Jung ◽

Yves Lansac ◽

...

Keyword(s):

Density Functional Theory ◽

Solar Cells ◽

Organic Solar Cells ◽

Density Functional ◽

Bulk Heterojunction ◽

Time Dependent ◽

Density Functional Theory Study ◽

Functional Theory ◽

Dependent Density

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Exploration of promising optical and electronic properties of (non-polymer) small donor molecules for organic solar cells

Scientific Reports ◽

10.1038/s41598-021-01070-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Muhammad Khalid ◽

Muhammad Usman Khan ◽

Saeed Ahmed ◽

Zahid Shafiq ◽

Mohammed Mujahid Alam ◽

...

Keyword(s):

Density Functional Theory ◽

Solar Cells ◽

Organic Solar Cells ◽

Density Functional ◽

Reorganization Energy ◽

Energy Difference ◽

Open Circuit ◽

Frontier Molecular Orbital ◽

Functional Theory ◽

Td Dft

AbstractNon-fullerene based organic compounds are considered promising materials for the fabrication of modern photovoltaic materials. Non-fullerene-based organic solar cells comprise of good photochemical and thermal stability along with longer device lifetimes as compared to fullerene-based compounds. Five new non-fullerene donor molecules were designed keeping in view the excellent donor properties of 3-bis(4-(2-ethylhexyl)-thiophen-2-yl)-5,7-bis(2ethylhexyl) benzo[1,2-:4,5-c′]-dithiophene-4,8-dione thiophene-alkoxy benzene-thiophene indenedione (BDD-IN) by end-capped modifications. Photovoltaic and electronic characteristics of studied molecules were determined by employing density functional theory (DFT) and time dependent density functional theory (TD-DFT). Subsequently, obtained results were compared with the reference molecule BDD-IN. The designed molecules presented lower energy difference (ΔΕ) in the range of 2.17–2.39 eV in comparison to BDD-IN (= 2.72 eV). Moreover, insight from the frontier molecular orbital (FMO) analysis disclosed that central acceptors are responsible for the charge transformation. The designed molecules were found with higher λmax values and lower transition energies than BDD-IN molecule due to stronger end-capped acceptors. Open circuit voltage (Voc) was observed in the higher range (1.54–1.78 V) in accordance with HOMOdonor–LUMOPC61BM by designed compounds when compared with BDD-IN (1.28 V). Similarly, lower reorganization energy values were exhibited by the designed compounds in the range of λe(0.00285–0.00370 Eh) and λh(0.00847–0.00802 Eh) than BDD-IN [λe(0.00700 Eh) and λh(0.00889 Eh)]. These measurements show that the designed compounds are promising candidates for incorporation into solar cell devices, which would benefit from better hole and electron mobility.

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Modeling the Electronic and OpƟ cal Processes in Organic Solar Cells: Density Functional Theory and Beyond

Organic Solar Cells ◽

10.1201/b17301-15 ◽

2014 ◽

pp. 555-606

Keyword(s):

Density Functional Theory ◽

Solar Cells ◽

Organic Solar Cells ◽

Density Functional ◽

Functional Theory

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Designing small organic non-fullerene acceptor molecules with diflorobenzene or quinoline core and dithiophene donor moiety through density functional theory

Scientific Reports ◽

10.1038/s41598-021-97662-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ghulam Bary ◽

Lubna Ghani ◽

Muhammad Imran Jamil ◽

Muhammad Arslan ◽

Waqar Ahmed ◽

...

Keyword(s):

Density Functional Theory ◽

Solar Cells ◽

Band Gap ◽

Gas Phase ◽

Organic Solar Cells ◽

Density Functional ◽

Excitation Energies ◽

Functional Theory ◽

Reorganization Energies ◽

Donor Moiety

AbstractThe non-fullerene acceptors A1–A5 with diflourobenzene or quinoline core (bridge) unit, donor cyclopenta[1,2-b:3,4-b′]dithiophene unit and 2-(2-methylene-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile as acceptor unit with additional phenyl, fulvene or thieno[3,2-d]pyrimidinyl 5-oxide groups have been designed through DFT calculations. The optimization of molecular geometries were performed with density functional theory (DFT) at B3LYP 6-31G (d,p) level of theory. The frontier molecular orbital (FMO) energies, band gap energies and dipole moments (ground and excited state) have been calculated to probe the photovoltaic properties. The band gap (1.42–2.01 eV) and dipole moment values (5.5–18. Debye) showed that these designed acceptors are good candidates for organic solar cells. Time-Dependent Density Functional Theory (TD-DFT) results showed λmax (wave length at maximum absorption) value (611–837 nm), oscillator strength (f) and excitation energies (1.50–2.02 eV) in gas phase and in CHCl3 solvent (1.48–1.89 eV) using integral equation formalism variant (IEFPCM) model. The λmax in CHCl3 showed marginal red shift for all designed acceptors compared with gas phase absorption. The partial density of states (PDOS) has been plotted by using multiwfn which showed that all the designed molecules have more electronic distribution at the donor moiety and lowest at the central bridge. The reorganization energies of electron (λe) (0.0007 eV to 0.017 eV), and the hole reorganization energy values (0.0003 eV to − 0.0403 eV) were smaller which suggested that higher charged motilities. The blends of acceptors A1–A5 with donor polymer D1 provided open circuit voltage (Voc) and ∆HOMO off-set of the HOMO of donor and acceptors. These blends showed 1.04 to 1.5 eV values of Voc and 0 to 0.38 eV ∆HOMO off set values of the donor–acceptor bends which indicate improved performance of the cell. Finally, the blend of D1–A4 was used for the study of distribution of HOMO and LUMO. The HOMO were found distributed on the donor polymer (D1) while the A4 acceptor was found with LUMO distribution. Based on λmax values, and band gap energies (Eg), excitation energies (Ex), reorganization energies; the A3 and A4 will prove good acceptor molecules for the development of organic solar cells.

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Characterization of the structural, mechanical, and electronic properties of fullerene mixtures: a molecular simulations description

Journal of Materials Chemistry C ◽

10.1039/c7tc03820h ◽

2018 ◽

Vol 6 (14) ◽

pp. 3642-3650 ◽

Cited By ~ 4

Author(s):

Naga Rajesh Tummala ◽

Saadullah G. Aziz ◽

Veaceslav Coropceanu ◽

Jean-Luc Bredas

Keyword(s):

Molecular Dynamics ◽

Density Functional Theory ◽

Solar Cells ◽

Electronic Properties ◽

Organic Solar Cells ◽

Density Functional ◽

Molecular Simulations ◽

Functional Theory ◽

Fullerene Derivatives

We investigate mixtures of fullerenes and fullerene derivatives, the most commonly used electron accepting materials in organic solar cells, by using a combination of molecular dynamics and density functional theory methods.

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