Unsymmetrical Squaraine Dyes for Dye-Sensitized Solar Cells: Position of the Anchoring Group Controls the Orientation and Self-Assembly of Sensitizers on the TiO2 Surface and Modulates Its Flat Band Potential

In an effort to provide, assess, and evaluate a theoretical approach which enables designing efficient donor-acceptor dye systems, the electronic structure and optical properties of pyran-squaraine as donor-acceptor dyes used in dye-sensitized solar cells were investigated. Ground state properties have been computed at the B3LYP/6-31+G**level of theory. The long-range corrected density functionals CAM-B3LYP, PBEPBE, PBE1PBE (PBE0), and TPSSH with 6-311++G**were employed to examine absorption properties of the studied dyes. In an extensive comparison between experimental results and ab initio benchmark calculations, the TPSSH functional with 6-311++G**basis set was found to be the most appropriate in describing the electronic properties for the studied pyran and squaraine dyes. Natural transition orbitals (NTO), frontier molecular orbitals (FMO), LUMO, HOMO, and energy gaps, of these dyes, have been analyzed to show their effect on the process of electron injection and dye regeneration. Interaction between HOMO and LUMO of pyran and squaraine dyes was investigated to understand the recombination process and charge-transfer process involving these dyes. Additionally, we performed natural bond orbital (NBO) analysis to investigate the role of charge delocalization and hyperconjugative interactions in the stability of the molecule.

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A Hydroxamic Acid Anchoring Group for Durable Dye-Sensitized Solar Cells Incorporating a Cobalt Redox Shuttle

ChemSusChem ◽

10.1002/cssc.201701157 ◽

2017 ◽

Vol 10 (17) ◽

pp. 3347-3351 ◽

Cited By ~ 23

Author(s):

Tomohiro Higashino ◽

Yuma Kurumisawa ◽

Ning Cai ◽

Yamato Fujimori ◽

Yukihiro Tsuji ◽

...

Keyword(s):

Solar Cells ◽

Hydroxamic Acid ◽

Dye Sensitized Solar Cells ◽

Dye Sensitized ◽

Redox Shuttle ◽

Anchoring Group ◽

Sensitized Solar Cells

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ChemInform Abstract: Simple Oligothiophene-Based Dyes for Dye-Sensitized Solar Cells (DSSCs): Anchoring Group Effects on Molecular Properties and Solar Cell Performance

ChemInform ◽

10.1002/chin.201134187 ◽

2011 ◽

Vol 42 (34) ◽

pp. no-no

Author(s):

Eigo Miyazaki ◽

Takashi Okanishi ◽

Yuki Suzuki ◽

Nozomi Ishine ◽

Hiroki Mori ◽

...

Keyword(s):

Solar Cells ◽

Solar Cell ◽

Dye Sensitized Solar Cells ◽

Molecular Properties ◽

Cell Performance ◽

Solar Cell Performance ◽

Dye Sensitized ◽

Anchoring Group ◽

Sensitized Solar Cells ◽

Group Effects

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Role of Pristine and Acid-Functionalized Fullerene on Breaking Dye Aggregates and its Impact on the Efficiency of Solar Cells

Australian Journal of Chemistry ◽

10.1071/ch13608 ◽

2014 ◽

Vol 67 (5) ◽

pp. 819

Author(s):

Syed Mujtaba Shah ◽

Zafar Iqbal ◽

Muzaffar Iqbal ◽

Naila Shahzad ◽

Amina Hana ◽

...

Keyword(s):

Solar Cells ◽

Zno Nanoparticles ◽

Self Assembly ◽

Zno Nanorods ◽

Active Material ◽

Dye Sensitized Solar Cells ◽

Dye Sensitized ◽

Transmission Electron ◽

Sensitized Solar Cells

Porphyrin dyes have an inherent tendency to aggregate. This leads to a self-quenching phenomenon that hinders electron transfer to the conduction band of semiconductors in dye-sensitized solar cells. Self-quenching adversely affects the efficiency of solar cells. Here, we report the interaction of porphyrin with pristine and acid-functionalized fullerene molecules on the surface of ZnO nanoparticles under chemisorbed conditions. Chemisorption of porphyrin only on ZnO nanoparticles instigates aggregation of the porphyrin molecules. These aggregates can be effectively broken by chemisorbing fullerene molecules on the surface of the ZnO nanoparticles. This is due to self-assembly formation processes because of porphyrin–fullerene interactions. The nanohybrid material, consisting of ZnO nanorods, acid-functionalized porphyrin, and fullerene derivatives, was characterized by UV–visible spectroscopy, fourier transform infrared spectroscopy, fluorescence spectroscopy, and transmission electron microscopy. The material generates better performing dye-sensitized solar cells when compared with those fabricated from porphyrin-based photo-active material.

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New Oxindole-Bridged Acceptors for Organic Sensitizers: Substitution and Performance Studies in Dye-Sensitized Solar Cells

Molecules ◽

10.3390/molecules25092159 ◽

2020 ◽

Vol 25 (9) ◽

pp. 2159

Author(s):

Yogesh S. Tingare ◽

Chaochin Su ◽

Ming-Tai Shen ◽

Sheng-Han Tsai ◽

Shih-Yu Ho ◽

...

Keyword(s):

Solar Cells ◽

Performance Studies ◽

Dye Sensitized Solar Cells ◽

Tio2 Surface ◽

Carbonyl Groups ◽

Dye Sensitized ◽

Amide Carbonyl ◽

And Performance ◽

Sensitized Solar Cells ◽

Organic Sensitizers

New D-π-A configured organic sensitizers featuring halogen-substituted oxindole-bridged acceptor units have been synthesized for dye-sensitized solar cells applications. Among fluorine, bromine, and iodine substitution, the cell based on bromine incorporated dye exhibited the highest efficiency. The oxindoles in these sensitizers were found to assist the electron injection through the chelation of their amide carbonyl groups to the TiO2 surface. This study provides an alternate approach for future rational dye design to gain excellent DSSC performance.

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Acid Treatment of Titania Pastes to Create Scattering Layers in Dye-Sensitized Solar Cells

International Journal of Photoenergy ◽

10.1155/2012/637839 ◽

2012 ◽

Vol 2012 ◽

pp. 1-8 ◽

Cited By ~ 8

Author(s):

Trystan Watson ◽

Cecile Charbonneau ◽

Daniel Bryant ◽

David Worsley

Keyword(s):

Solar Cells ◽

Self Assembly ◽

Dye Sensitized Solar Cells ◽

Transparent Film ◽

Similar Function ◽

Short Term ◽

Acid Pretreatment ◽

Scattering Layer ◽

Dye Sensitized ◽

Sensitized Solar Cells

In dye-sensitized solar cells (DSC) scattering layers are used to increase the path length of light incident on the TiO2film. This is typically achieved by the deposition of an additional TiO2layer on top of an existing transparent film and designed to trap light. In this work we show that a simple acid pretreatment can lead to the formation of a scattering “skin” on the surface of a single TiO2film performing a similar function to a scattering layer without any additional depositions. This is important in increasing manufacturing throughput for DSCs as further TiO2depositions require additional materials and heat treatment. The pretreatment leads to self-assembly of a scattering layer of TiO2which covers the surface on short-term immersion (<30 min) and penetrates the bulk layer upon longer immersion. The method has been shown to increase the efficiency of the device by 20%.

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