scholarly journals Molecular engineering of indenoindene-3-ethylrodanine acceptors with A2-A1-D-A1-A2 architecture for promising fullerene-free organic solar cells

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Muhammad Khalid ◽  
Momina ◽  
Muhammad Imran ◽  
Muhammad Fayyaz ur Rehman ◽  
Ataualpa Albert Carmo Braga ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Solar Cells ◽  
Charge Transfer ◽  
Organic Solar Cells ◽  
Density Functional ◽  
Energy Gap ◽  
Molecular Engineering ◽  
Frontier Molecular Orbital ◽  
Functional Theory ◽  
Acceptor Molecules

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.

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

2015 ◽  
Vol 93 (11) ◽  
pp. 1181-1190 ◽  
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.

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

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.

scholarly journals Theoretical Study of a Class of Organic D-π-A Dyes for Polymer Solar Cells: Influence of Various π-Spacers

Crystals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 163
Author(s):  
Nguyen Van Trang ◽  
Tran Ngoc Dung ◽  
Ngo Tuan Cuong ◽  
Le Thi Hong Hai ◽  
Daniel Escudero ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Solar Cells ◽  
Molecular Orbital ◽  
Density Functional ◽  
Energy Gap ◽  
Polymer Solar Cells ◽  
Basis Set ◽  
Structure Theory ◽  
Functional Theory ◽  
Alkyl Groups

A class of D-π-A compounds that can be used as dyes for applications in polymer solar cells has theoretically been designed and studied, on the basis of the dyes recently shown by experiment to have the highest power conversion efficiency (PCE), namely the poly[4,8-bis(5-(2-butylhexylthio)thiophen-2-yl)benzo[1,2-b:4,5-b’]dithiophene-2,6-diyl-alt-TZNT] (PBDTS-TZNT) and poly[4,8-bis(4-fluoro-5-(2-butylhexylthio)thiophen-2-yl)benzo[1,2-b:4,5-b’]dithiophene-2,6-diyl-alt-TZNT] (PBDTSF-TZNT) substances. Electronic structure theory computations were carried out with density functional theory and time-dependent density functional theory methods in conjunction with the 6−311G (d, p) basis set. The PBDTS donor and the TZNT (naphtho[1,2-c:5,6-c]bis(2-octyl-[1,2,3]triazole)) acceptor components were established from the original substances upon replacement of long alkyl groups within the thiophene and azole rings with methyl groups. In particular, the effects of several π-spacers were investigated. The calculated results confirmed that dithieno[3,2-b:2′,3′-d] silole (DTS) acts as an excellent π-linker, even better than the thiophene bridge in the original substances in terms of well-known criteria. Indeed, a PBDTS-DTS-TZNT combination forms a D-π-A substance that has a flatter structure, more rigidity in going from the neutral to the cationic form, and a better conjugation than the original compounds. The highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) energy gap of such a D-π-A substance becomes smaller and its absorption spectrum is more intense and red-shifted, which enhances the intramolecular charge transfer and makes it a promising candidate to attain higher PCEs.

scholarly journals Towards Rational Designing of Efficient Sensitizers Based on Thiophene and Infrared Dyes for Dye-Sensitized Solar Cells

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Ahmad Irfan ◽  
Abdullah G. Al-Sehemi ◽  
Shabbir Muhammad
Keyword(s):  
Density Functional Theory ◽  
Solar Cells ◽  
Molecular Orbital ◽  
Density Functional ◽  
Energy Gap ◽  
Dye Sensitized Solar Cells ◽  
Functional Theory ◽  
Dye Sensitized ◽  
Orbital Energies ◽  
Sensitized Solar Cells

Geometries, electronic properties, and absorption spectra of the dyes which are a combination of thiophene based dye (THPD) and IR dyes (covering IR region; TIRBD1-TIRBD3) were performed using density functional theory (DFT) and time dependent density functional theory (TD-DFT), respectively. Different electron donating groups, electron withdrawing groups, and IR dyes have been substituted on THPD to enhance the efficiency. The bond lengths of new designed dyes are almost the same. The lowest unoccupied molecular orbital energies of designed dyes are above the conduction band of TiO2 and the highest occupied molecular orbital energies are below the redox couple revealing that TIRBD1-TIRBD3 would be better sensitizers for dye-sensitized solar cells. The broad spectra and low energy gap also showed that designed materials would be efficient sensitizers.

scholarly journals Electronic structures and photovoltaic properties of a novel phthalocyanine and titanium dioxide phthalocyanine for dye sensitized-solar cells

2021 ◽  
Vol 6 (3) ◽  
pp. 107-115
Author(s):  
Fares A. Yasseen ◽  
Faeq A. Al-Temimei
Keyword(s):  
Density Functional Theory ◽  
Solar Cells ◽  
Electronic Structures ◽  
Density Functional ◽  
Energy Gap ◽  
Dye Sensitized Solar Cells ◽  
Solar Spectrum ◽  
Electron Injection ◽  
Basis Set ◽  
Functional Theory

In the present work, geometries, electronic structures, photovoltaic and optical properties have been carried out on a series of structures formation of phthalocyanine and Titanylphthalocyanine dyes, which are replaced by several subgroup. A density functional theory (DFT) approach together with hybrid function (B3LYP) at SDD basis set was used for the ground state properties in the gas phase. The time-dependent density functional theory (TD-DFT)/ B3LYP was used to investigate the excitation properties of new dyes and analyzed the trends in their optical and redox characteristics. Theoretical principles of HOMO and LUMO energy levels of dyes is requisite in analyzing organic solar cells, thus, HOMO, LUMO levels, open circuit voltage, energy gap, light harvestings efficiency, electron regeneration and electron injection have been calculated and discussed. The outcome of the efficiency, the considered dyes explain absorption energy and wavelength properties that correspond to the solar spectrum requirements. According to results, all the considered materials have a good property and possibility of electron injection procedure from the dyes to conduction band of TiO2, PC60BM or PC60BM. As a result, the molecular changes affect the electronic properties of dye molecules for solar cells. Also, a study of new dyes sensitizers showed that designed materials will be excellent sensitizers. Theoretical designing will prae a way for experimentalists to synthesize the efficient sensitizers for solar cells clearer.

Accurate description of hybridized local and charge-transfer excited-state in donor–acceptor molecules using density functional theory

RSC Advances ◽  
2016 ◽  
Vol 6 (110) ◽  
pp. 108404-108410 ◽  
Author(s):  
Y. Y. Pan ◽  
J. Huang ◽  
Z. M. Wang ◽  
S. T. Zhang ◽  
D. W. Yu ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Excited State ◽  
Charge Transfer ◽  
Ground State ◽  
Density Functional ◽  
Accurate Description ◽  
Functional Theory ◽  
Donor Acceptor ◽  
Acceptor Molecules

The ωB97X was the most reliable functional for the accurate description of HLCT state at ground state and excited state.

scholarly journals Structure, electronic and optical properties of chalcopyrite-type nano-clusters XFeY2 (X=Cu, Ag, Au; Y=S, Se, Te): a density functional theory study

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Prabhat Ranjan ◽  
Praveen K. Surolia ◽  
Tanmoy Chakraborty
Keyword(s):  
Density Functional Theory ◽  
Dielectric Constant ◽  
Refractive Index ◽  
Optical Properties ◽  
Solar Cells ◽  
Density Functional ◽  
Energy Gap ◽  
Lumo Energy ◽  
Functional Theory ◽  
Homo Lumo

Abstract Iron-based chalcopyrite materials have diverse applications in solar cells, spintronic, thermoelectric devices, LEDs and medical sciences. In this report we have studied structure, electronic and optical properties of chalcopyrite-type nano-cluster XFeY2 (X=Cu, Ag, Au; Y=S, Se, Te) systematically by using Density Functional Theory (DFT). Our computed HOMO-LUMO energy gap of XFeY2 is in the range of 1.568–3.982 eV, which endorses its potential application in optoelectronic devices and solar cells. The result shows that chalcopyrite-type material AuFeS2 having a star-type structure with point group C2v and sextet spin multiplicity, is the most stable cluster with HOMO-LUMO energy gap of 3.982 eV. The optical properties viz. optical electronegativity, refractive index, dielectric constant, IR and Raman activity of these nano-clusters are also investigated. The result exhibits that HOMO-LUMO energy gap of XFeY2 along with optical electronegativity and vibrational frequency decreases from S to Se to Te, whereas refractive index and dielectric constant increases in the reverse order.

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