Synergistic Effects of Processing Additives and Thermal Annealing on Nanomorphology and Hole Mobility of Poly(3-hexylthiophene) Thin Films

Control of the nanoscale molecular ordering and charge-carrier mobility of poly(3-hexylthiophene-2,5-diyl) (P3HT) was achieved by the combined use of processing additives and thermal annealing. Evaluation of four processing additives (1,8-octanedithiol (ODT), diphenyl ether (DPE), 1-chloronaphthalene (CN), and 1,8-diiodooctane (DIO), which are commonly used for the fabrication of organic solar cells, revealed that the nanoscale molecular ordering and, therefore, the charge-carrier mobility, are largely affected by the additives, as demonstrated by spectral absorption, X-ray diffraction, and atomic force microscopy. Thermal annealing selectively influenced the morphological changes, depending on the solubility of P3HT in the additive at high temperature. In the case of CN, in which P3HT can be dissolved at moderate temperature, significant molecular ordering was observed even without thermal annealing. For DIO, in which P3HT is only soluble at elevated temperature, the mobility reached 1.14 × 10−1 cm2 V−1 s−1 only after annealing. ODT and DPE were not effective as processing additives in a single-component P3HT. This study provides insight for designing the processing conditions to control the morphology and charge-transport properties of polymers.

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Effects of Solvent Vapor Annealing on Morphology and Charge Transport of Poly(3-hexylthiophene) (P3HT) Films Incorporated with Preformed P3HT Nanowires

Polymers ◽

10.3390/polym12051188 ◽

2020 ◽

Vol 12 (5) ◽

pp. 1188

Author(s):

Mingu Jang ◽

Yang-Il Huh ◽

Mincheol Chang

Keyword(s):

Thin Films ◽

Charge Transport ◽

Carrier Mobility ◽

Morphological Changes ◽

Charge Carrier Mobility ◽

Solvent Vapor ◽

Molecular Ordering ◽

Vapor Annealing ◽

Solvent Vapor Annealing ◽

Influence Of Solvent

We systematically studied the influence of solvent vapor annealing on the molecular ordering, morphologies, and charge transport properties of poly(3-hexylthiophene) (P3HT) thin films embedded with preformed crystalline P3HT nanowires (NWs). Solvent vapor annealing (SVA) with chloroform (CF) was found to profoundly impact on the structural and morphological changes, and thus on the charge transport characteristics, of the P3HT-NW-embedded P3HT films. With increased annealing time, the density of crystalline P3HT NWs was increased within the resultant films, and also intra- and intermolecular interactions of the corresponding films were significantly improved. As a result, the P3HT-NW-embedded P3HT films annealed with CF vapor for 20 min resulted in a maximized charge carrier mobility of ~0.102 cm2 V−1 s−1, which is higher than that of pristine P3HT films by 4.4-fold (μ = ~0.023 cm2 V−1 s−1).

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Elucidation of Donor:Acceptor Phase Separation in Nonfullerene Organic Solar Cells and Its Implications on Device Performance and Charge Carrier Mobility

ACS Applied Energy Materials ◽

10.1021/acsaem.9b01534 ◽

2019 ◽

Vol 2 (10) ◽

pp. 7535-7545 ◽

Cited By ~ 4

Author(s):

Sebastian F. Hoefler ◽

Georg Haberfehlner ◽

Thomas Rath ◽

Andreas Keilbach ◽

Mathias A. Hobisch ◽

...

Keyword(s):

Solar Cells ◽

Phase Separation ◽

Charge Carrier ◽

Organic Solar Cells ◽

Carrier Mobility ◽

Charge Carrier Mobility ◽

Device Performance

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A theoretical study of influence of charge carrier mobility in PTB7:PC71BM bulk heterojunction organic solar cells

Optical and Quantum Electronics ◽

10.1007/s11082-016-0780-y ◽

2016 ◽

Vol 48 (11) ◽

Cited By ~ 1

Author(s):

S. Nazerdeylami ◽

H. Rezagholipour Dizaji

Keyword(s):

Solar Cells ◽

Charge Carrier ◽

Organic Solar Cells ◽

Carrier Mobility ◽

Theoretical Study ◽

Bulk Heterojunction ◽

Charge Carrier Mobility

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Extraction Current Transients for Selective Charge-Carrier Mobility Determination in Non-Fullerene and Ternary Bulk Heterojunction Organic Solar Cells

ACS Applied Energy Materials ◽

10.1021/acsaem.0c01539 ◽

2020 ◽

Vol 3 (9) ◽

pp. 9190-9197

Author(s):

Staffan Dahlström ◽

Xiaoyu Liu ◽

Yajie Yan ◽

Oskar J. Sandberg ◽

Mathias Nyman ◽

...

Keyword(s):

Solar Cells ◽

Charge Carrier ◽

Organic Solar Cells ◽

Carrier Mobility ◽

Bulk Heterojunction ◽

Charge Carrier Mobility ◽

Ternary Bulk Heterojunction ◽

Current Transients

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Charge carrier mobility dynamics in organic semiconductors and solar cells

Lithuanian Journal of Physics ◽

10.3952/physics.v60i1.4160 ◽

2020 ◽

Vol 60 (1) ◽

Author(s):

Vidmantas Gulbinas

Keyword(s):

Solar Cells ◽

Charge Carrier ◽

Organic Semiconductors ◽

Organic Solar Cells ◽

Carrier Mobility ◽

Charge Carrier Mobility ◽

Charge Carriers ◽

Organic Layer ◽

Stoichiometric Ratio ◽

Donor And Acceptor

Charge carrier mobility in organic semiconductors is not a constant value unambigously characterizing some particular material, but depends on the electric field, temperature and even on time after it was generated or injected. The time dependence is particularly important for the thin-film devices where charge carriers pass the organic layer before mobility reaching its stationary value. Here we give a review of experimental techniques with ultrafast timeresolution enabling one to address the mobility kinetics and analyse properties of the time-dependent mobility in conjugated polymers and organic solar cells. We analyse kinetics during the charge carrier generation and extraction of free charge carriers. The mobility typically decreases by several orders of magnitude on a picosecond-nanosecond time scale; however, its kinetics also depends on the investigation technique. The mobility kinetics in blends for bulk heterojunction solar cells strongly depends on the stoichiometric ratio of donor and acceptor materials.

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Impact of Charge Carrier Mobility and Electrode Selectivity on the Performance of Organic Solar Cells

Elementary Processes in Organic Photovoltaics - Advances in Polymer Science ◽

10.1007/978-3-319-28338-8_17 ◽

2016 ◽

pp. 401-418

Author(s):

Annika Spies ◽

Jeneke Reinhardt ◽

Mathias List ◽

Birger Zimmermann ◽

Uli Würfel

Keyword(s):

Solar Cells ◽

Charge Carrier ◽

Organic Solar Cells ◽

Carrier Mobility ◽

Charge Carrier Mobility ◽

Electrode Selectivity

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Charge carrier mobility and electronic properties of Al(Op)3: impact of excimer formation

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.6.112 ◽

2015 ◽

Vol 6 ◽

pp. 1107-1115 ◽

Cited By ~ 6

Author(s):

Andrea Magri ◽

Pascal Friederich ◽

Bernhard Schäfer ◽

Valeria Fattori ◽

Xiangnan Sun ◽

...

Keyword(s):

Thin Film ◽

Charge Carrier ◽

Transport Properties ◽

Electron Mobility ◽

Carrier Mobility ◽

Hole Mobility ◽

Charge Carrier Mobility ◽

The Other ◽

Theoretical Simulation ◽

Excimer Formation

We have studied the electronic properties and the charge carrier mobility of the organic semiconductor tris(1-oxo-1H-phenalen-9-olate)aluminium(III) (Al(Op)3) both experimentally and theoretically. We experimentally estimated the HOMO and LUMO energy levels to be −5.93 and −3.26 eV, respectively, which were close to the corresponding calculated values. Al(Op)3 was successfully evaporated onto quartz substrates and was clearly identified in the absorption spectra of both the solution and the thin film. A structured steady state fluorescence emission was detected in solution, whereas a broad, red-shifted emission was observed in the thin film. This indicates the formation of excimers in the solid state, which is crucial for the transport properties. The incorporation of Al(Op)3 into organic thin film transistors (TFTs) was performed in order to measure the charge carrier mobility. The experimental setup detected no electron mobility, while a hole mobility between 0.6 × 10−6 and 2.1 × 10−6 cm2·V−1·s−1 was measured. Theoretical simulations, on the other hand, predicted an electron mobility of 9.5 × 10−6 cm2·V−1·s−1 and a hole mobility of 1.4 × 10−4 cm2·V−1·s−1. The theoretical simulation for the hole mobility predicted an approximately one order of magnitude higher hole mobility than was observed in the experiment, which is considered to be in good agreement. The result for the electron mobility was, on the other hand, unexpected, as both the calculated electron mobility and chemical common sense (based on the capability of extended aromatic structures to efficiently accept and delocalize additional electrons) suggest more robust electron charge transport properties. This discrepancy is explained by the excimer formation, whose inclusion in the multiscale simulation workflow is expected to bring the theoretical simulation and experiment into agreement.

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Modelling of the charge carrier mobility in disordered linear polymer materials

Physical Chemistry Chemical Physics ◽

10.1039/c6cp07789g ◽

2017 ◽

Vol 19 (11) ◽

pp. 7760-7771 ◽

Cited By ~ 17

Author(s):

Petr Toman ◽

Miroslav Menšík ◽

Wojciech Bartkowiak ◽

Jiří Pfleger

Keyword(s):

Charge Carrier ◽

Concentration Dependence ◽

Carrier Mobility ◽

Hole Mobility ◽

Charge Carrier Mobility ◽

Linear Polymer ◽

Polymer Materials ◽

P Concentration ◽

Energetic Disorder

Concentration dependence of the hole mobility in the crystalline and amorphous P3HT calculated for different values of the local energetic disorder σε.

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