Effects of Side-Chain Engineering with the S Atom in Thieno[3,2-b]thiophene-porphyrin to Obtain Small-Molecule Donor Materials for Organic Solar Cells

To explore the effect of the introduction of heteroatoms on the properties of porphyrin materials, a new porphyrin-based derivative small-molecule donor named as PorTT-T was designed and synthesized based on alkyl-thieno[3,2-b]thiophene(TT)-substituted porphyrins. The linker bridge and end groups of PorTT-T were the same as those of XLP-II small-molecule donor materials, while the side-chain attached to the core of thieno[3,2-b]thiophene(TT)-substituted porphyrin was different. Measurements of intrinsic properties showed that PorTT-T has wide absorption and appropriate energy levels in the UV-visible range. A comparison of the morphologies of the two materials using atomic force microscopy showed that PorTT-T has a better surface morphology with a smaller root-mean-square roughness, and can present closer intermolecular stacking as compared to XLP-II. The device characterization results showed that PorTT-T with the introduced S atom has a higher open circuit voltage of 0.886 eV, a higher short circuit current of 12.03 mAcm−2, a fill factor of 0.499, a high photovoltaic conversion efficiency of 5.32%, better external quantum efficiency in the UV-visible range, and higher hole mobility.

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An Improved Triple-Tandem Organic Solar Cell

MRS Proceedings ◽

10.1557/proc-1212-s03-19 ◽

2009 ◽

Vol 1212 ◽

Author(s):

Dewei Zhao ◽

Xiao Wei Sun ◽

Lin Ke ◽

Swee Tiam Tan

Keyword(s):

Solar Cell ◽

Small Molecule ◽

Organic Solar Cells ◽

Organic Solar Cell ◽

Copper Phthalocyanine ◽

Short Circuit ◽

Short Circuit Current ◽

Open Circuit ◽

Solar Irradiation ◽

The Third

AbstractWe present an efficient polymer-small molecule triple-tandem organic solar cell (OSC), consisting of poly(3-hexylthiophene) (P3HT) and 1-(3-methoxycarbonyl)-propyl-1-phenyl-(6,6)C61 (PCBM) bulk heterojunction as the first and second cells, and small molecules copper phthalocyanine (CuPc) and fullerene (C60) as the third cell on top. These sub-cells are connected by an intermediate layer of Al(1 nm)/MoO3(15 nm), which appears to be highly transparent, structurally smooth, and electrically functional. Compared to our previous all polymer triple-tandem organic solar cells (2.03%), this polymer-small molecule triple-tandem organic solar cell achieves an improved power conversion efficiency of 2.18% with a short-circuit current density (Jsc) = 3.02 mA/cm2, open-circuit voltage (Voc) = 1.51 V, and fill factor (FF) = 47.7% under simulated solar irradiation of 100 mW/cm2 (AM1.5G), which can be attributed to the increased photocurrent generation in the third cell since the third cell has the complementary absorption with two bottom cells despite a slightly reduced Voc.

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Fine‐Tuning the Energy Levels of a Nonfullerene Small‐Molecule Acceptor to Achieve a High Short‐Circuit Current and a Power Conversion Efficiency over 12% in Organic Solar Cells

Advanced Materials ◽

10.1002/adma.201704904 ◽

2017 ◽

Vol 30 (3) ◽

pp. 1704904 ◽

Cited By ~ 158

Author(s):

Bin Kan ◽

Jiangbin Zhang ◽

Feng Liu ◽

Xiangjian Wan ◽

Chenxi Li ◽

...

Keyword(s):

Solar Cells ◽

Power Conversion Efficiency ◽

Conversion Efficiency ◽

Small Molecule ◽

Organic Solar Cells ◽

Short Circuit ◽

Energy Levels ◽

Power Conversion ◽

Short Circuit Current ◽

Fine Tuning

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Over 14% efficiency nonfullerene all-small-molecule organic solar cells enabled by improving the ordering of molecular donors via side-chain engineering

Journal of Materials Chemistry A ◽

10.1039/d0ta01893g ◽

2020 ◽

Vol 8 (15) ◽

pp. 7405-7411 ◽

Cited By ~ 14

Author(s):

Jing Gao ◽

Jinfeng Ge ◽

Ruixiang Peng ◽

Chang Liu ◽

Liang Cao ◽

...

Keyword(s):

Solar Cells ◽

Small Molecule ◽

Current Density ◽

Organic Solar Cells ◽

Short Circuit ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Side Chain ◽

Highly Efficient

Improving the short-circuit current density (Jsc) is a big challenge for gaining highly efficient nonfullerene all-small-molecule organic solar cells (NFASM-OSCs).

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Study on the Crystal Size of PCBM in Organic Photovoltaic Cells

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.535-537.1258 ◽

2012 ◽

Vol 535-537 ◽

pp. 1258-1261

Author(s):

Nan Hai Sun ◽

Xiao Ying Chang

Keyword(s):

Phase Separation ◽

Organic Solar Cells ◽

Crystal Size ◽

Short Circuit ◽

Acid Methyl Ester ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Open Circuit ◽

Uv Visible ◽

Parallel Resistance

Phase separation of the poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester(PCBM) active layer (ATL) was investigated by varying their relative ratio in the organic solar cells (OSCs).With the help of the UV/visible spectrophotometer, optical microscopy and scanning electron microscope,we found that the cluster of PCBM at the interface or surface was affected by Al cathode, the composition of the blends and thermal annealing. The disc-like shape crystals of PCBM substituted for the needle-like ones at higher PCBM compositions at the ATL/Al interface, which led to stronger contacts and bigger contact area. It could make short circuit current density increase, but may affect the blend morphology and result in parallel resistance and open circuit voltage decreased with the PCBM ratio increasing from 40 to 60%. The microstructure of the P3HT:PCBM ATL, determined by the composition dependent phase separation, supported the optimized performance of the OSCs with the composition of 40–50% PCBM.

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Efficient Solar Cells Based on a Polymer Donor with β-Branching in Trialkylsilyl Side Chains

Organic Materials ◽

10.1055/s-0041-1726427 ◽

2021 ◽

Vol 03 (02) ◽

pp. 134-140

Author(s):

Haijun Bin ◽

Martijn M. Wienk ◽

René A. J. Janssen

Keyword(s):

Solar Cells ◽

Organic Solar Cells ◽

Short Circuit ◽

Energy Levels ◽

Short Circuit Current ◽

Open Circuit ◽

Side Chains ◽

Photovoltaic Properties ◽

Alkyl Groups ◽

High Efficient

Side-chain engineering is an important strategy in designing novel polymer semiconductor materials for high-efficient organic solar cells. The use of trialkylsilyl side chains can improve the photovoltaic efficiency by decreasing the energy of the HOMO of the polymer and improving its crystallinity and hole mobility. Compared to simple linear derivatives, α-branching in the alkyl groups of trialkylsilyl side chains causes strong aggregation and excessive phase separation in the photoactive layer, leading to poor device performance. β-Branching of the alkyl groups has not yet been used in trialkylsilyl side chains. Herein, we describe a new polymer (J77) with triisobutylsilyl side chains to investigate the effect of β-branching on the molecular aggregation, optical properties, energy levels, and photovoltaic properties. We find that compared to α-branching, β-branching of alkyl groups in trialkylsilyl side chains significantly reduces aggregation. This enables J77 to form blend morphologies in films that provide high-efficient solar cells in combination with different non-fullerene acceptors. Moreover β-branching of the alkyl groups in trialkylsilyl side chains lowers the HOMO energy level of J77 and increases the open-circuit voltage of J77-based solar cells without sacrificing short-circuit current density or fill factor.

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The Effect of Acceptor Content on the Efficiency of Organic Photovoltaic Cells

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.209-211.1801 ◽

2012 ◽

Vol 209-211 ◽

pp. 1801-1804

Author(s):

Jian Min Ye ◽

Nan Hai Sun

Keyword(s):

Phase Separation ◽

Organic Solar Cells ◽

Short Circuit ◽

Acid Methyl Ester ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Open Circuit ◽

Blend Morphology ◽

Uv Visible ◽

Parallel Resistance

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N,N-Diarylamino end-capping as a new strategy for simultaneously enhancing open-circuit voltage, short-circuit current density and fill factor in small molecule organic solar cells

RSC Advances ◽

10.1039/c5ra00770d ◽

2015 ◽

Vol 5 (27) ◽

pp. 20724-20733 ◽

Cited By ~ 17

Author(s):

Daobin Yang ◽

Youqin Zhu ◽

Yan Jiao ◽

Lin Yang ◽

Qianqian Yang ◽

...

Keyword(s):

Solar Cells ◽

Small Molecule ◽

Organic Solar Cells ◽

Fill Factor ◽

Short Circuit ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Open Circuit ◽

New Strategy ◽

End Capping

N,N-Diarylamino end-capping strategy for asymmetrical squaraines with simultaneously enhanced Voc, Jsc and FF in solution-processed small molecule organic solar cells.

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SCAPS Simulation on P3HT:Graphene Nanocomposites Based Bulk-Heterojunction Organic Solar Cells

International Journal of Electrical & Electronic Systems Research (IEESR) ◽

10.24191/ieesr.v9i1.950 ◽

2019 ◽

Vol 9 (1) ◽

pp. 28

Author(s):

Nur Shakina Mohd Shariff ◽

Puteri Sarah Mohamad Saad ◽

Mohamad Rusop Mahmood

Keyword(s):

Solar Cells ◽

Organic Solar Cells ◽

Fill Factor ◽

Bulk Heterojunction ◽

Short Circuit ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Open Circuit ◽

Simulation Software ◽

Capacitance Voltage

There has been an increasing interest towards organic solar cells after the discovery of conjugated polymer and bulk-heterojunction concept. Eventhough organic solar cells are less expensive than inorganic solar cells but the power conversion energy is still considered low. The main objective of this research is to investigate the effect of the P3HT’s thickness and concentration towards the efficiency of the P3HT:Graphene solar cells. A simulation software that is specialize for photovoltaic called SCAPS is used in this research to simulate the effect on the solar cells. The solar cell’s structure will be drawn inside the simulation and the parameters for each layers is inserted. The result such as the open circuit voltage (Voc), short circuit current density (Jsc), fill factor (FF), efficiency (η), capacitance-voltage (C-V) and capacitance-frequency (C-f) characteristic will be calculated by the software and all the results will be put into one graph.

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Molecular-level architectural design using benzothiadiazole-based polymers for photovoltaic applications

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.13.87 ◽

2017 ◽

Vol 13 ◽

pp. 863-873 ◽

Cited By ~ 8

Author(s):

Vinila N Viswanathan ◽

Arun D Rao ◽

Upendra K Pandey ◽

Arul Varman Kesavan ◽

Praveen C Ramamurthy

Keyword(s):

Molecular Orbital ◽

Architectural Design ◽

Density Functional ◽

Short Circuit ◽

Energy Levels ◽

Photovoltaic Performance ◽

Hole Mobility ◽

Short Circuit Current ◽

Open Circuit ◽

Lowest Unoccupied Molecular Orbital

A series of low band gap, planar conjugated polymers, P1 (PFDTBT), P2 (PFDTDFBT) and P3 (PFDTTBT), based on fluorene and benzothiadiazole, was synthesized. The effect of fluorine substitution and fused aromatic spacers on the optoelectronic and photovoltaic performance was studied. The polymer, derived from dithienylated benzothiodiazole and fluorene, P1, exhibited a highest occupied molecular orbital (HOMO) energy level at −5.48 eV. Density functional theory (DFT) studies as well as experimental measurements suggested that upon substitution of the acceptor with fluorine, both the HOMO and lowest unoccupied molecular orbital (LUMO) energy levels of the resulting polymer, P2, were lowered, leading to a higher open circuit voltage and short circuit current with an overall improvement of more than 110% for the photovoltaic devices. Moreover, a decrease in the torsion angle between the units was also observed for the fluorinated polymer P2 due to the enhanced electrostatic interaction between the fluorine substituents and sulfur atoms, leading to a high hole mobility. The use of a fused π-bridge in polymer P3 for the enhancement of the planarity as compared to the P1 backbone was also studied. This enhanced planarity led to the highest observed mobility among the reported three polymers as well as to an improvement in the device efficiency by more than 40% for P3.

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An asymmetric small molecule acceptor for organic solar cells with a short circuit current density over 24 mA cm−2

Journal of Materials Chemistry A ◽

10.1039/d0ta01636e ◽

2020 ◽

Vol 8 (31) ◽

pp. 15984-15991 ◽

Cited By ~ 4

Author(s):

Fangfang Cai ◽

Hongjian Peng ◽

Honggang Chen ◽

Jun Yuan ◽

Jiefeng Hai ◽

...

Keyword(s):

Solar Cells ◽

Small Molecule ◽

Current Density ◽

Organic Solar Cells ◽

Short Circuit ◽

Short Circuit Current ◽

Short Circuit Current Density

Acceptor Y22 with an asymmetric hexacyclic A–DA′D–A structure achieved a high PCE of 15.4% and a high Jsc of 24.37 mA cm−2, which are among the best values reported for asymmetric acceptor based binary organic solar cells.

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