1
|
Bölke S, Keller T, Trilling F, Forster M, Scherf U, Chassé T, Peisert H. The Influence of the Side Chain Structure on the Photostability of Low Band Gap Polymers. Molecules 2023; 28:molecules28093858. [PMID: 37175268 PMCID: PMC10180311 DOI: 10.3390/molecules28093858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 04/17/2023] [Accepted: 04/27/2023] [Indexed: 05/15/2023] Open
Abstract
Side chains play an important role in the photo-oxidation process of low band gap (LBG) polymers. For example, it has been shown that their photostability can be increased by the introduction of aromatic-oxy-alkyl links. We studied the photostability of prototypical LBG polymers with alkyl and oxyalkyl side chains during irradiation with white light (AM 1.5 conditions) in dry air using UV/vis and IR spectroscopy. Though its degradation kinetics were distinctly affected by the presence or absence of oxygen in the structure of the side chains, in particular cases, the stability was more affected by the presence of linear or branched side chains. Moreover, we showed that the exact position of the alkyl/oxyalkyl side chain at the polymer backbone could be crucial. Although minor effects of chemical modifications on the electronic parameters (ionization potential and gap) were observed, the molecular orientation, determined by polarization modulation-infrared reflection-absorption spectroscopy (PMIRRAS), could be affected. The aggregation and crystallinity of these polymers may distinctly affect their stability.
Collapse
Affiliation(s)
- Sven Bölke
- Institut für Physikalische und Theoretische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Tina Keller
- Makromolekulare Chemie (buwMakro) und Wuppertal Center for Smart Materials and Systems (CM@S), Bergische Universität Wuppertal, Gaussstrasse 20, 42119 Wuppertal, Germany
| | - Florian Trilling
- Makromolekulare Chemie (buwMakro) und Wuppertal Center for Smart Materials and Systems (CM@S), Bergische Universität Wuppertal, Gaussstrasse 20, 42119 Wuppertal, Germany
| | - Michael Forster
- Makromolekulare Chemie (buwMakro) und Wuppertal Center for Smart Materials and Systems (CM@S), Bergische Universität Wuppertal, Gaussstrasse 20, 42119 Wuppertal, Germany
| | - Ullrich Scherf
- Makromolekulare Chemie (buwMakro) und Wuppertal Center for Smart Materials and Systems (CM@S), Bergische Universität Wuppertal, Gaussstrasse 20, 42119 Wuppertal, Germany
| | - Thomas Chassé
- Institut für Physikalische und Theoretische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Heiko Peisert
- Institut für Physikalische und Theoretische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| |
Collapse
|
2
|
Jessop IA, Chong A, Graffo L, Camarada MB, Espinoza C, Angel FA, Saldías C, Tundidor-Camba A, Terraza CA. Synthesis and Characterization of a 2,3-Dialkoxynaphthalene-Based Conjugated Copolymer via Direct Arylation Polymerization (DAP) for Organic Electronics. Polymers (Basel) 2020; 12:E1377. [PMID: 32575423 PMCID: PMC7362231 DOI: 10.3390/polym12061377] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 06/12/2020] [Accepted: 06/15/2020] [Indexed: 11/16/2022] Open
Abstract
Poly[(5,5'-(2,3-bis(2-ethylhexyloxy)naphthalene-1,4-diyl)bis(thiophene-2,2'-diyl))-alt-(2,1,3-benzothiadiazole-4,7-diyl)] (PEHONDTBT) was synthesized for the first time and through direct arylation polymerization (DAP) for use as p-donor material in organic solar cells. Optimized reaction protocol leads to a donor-acceptor conjugated polymer in good yield, with less structural defects than its analog obtained from Suzuki polycondensation, and with similar or even higher molecular weight than other previously reported polymers based on the 2,3-dialkoxynaphthalene monomer. The batch-to-batch repeatability of the optimized DAP conditions for the synthesis of PEHONDTBT was proved, showing the robustness of the synthetic strategy. The structure of PEHONDTBT was corroborated by NMR, exhibiting good solubility in common organic solvents, good film-forming ability, and thermal stability. PEHONDTBT film presented an absorption band centered at 498 nm, a band gap of 2.15 eV, and HOMO and LUMO energy levels of -5.31 eV and -3.17 eV, respectively. Theoretical calculations were performed to understand the regioselectivity in the synthesis of PEHONDTBT and to rationalize its optoelectronic properties. Bilayer heterojunction organic photovoltaic devices with PEHONDTBT as the donor layer were fabricated to test their photovoltaic performance, affording low power-conversion efficiency in the preliminary studies.
Collapse
Affiliation(s)
- Ignacio A. Jessop
- Organic and Polymeric Materials Research Laboratory, Facultad de Ciencias, Universidad de Tarapacá, P.O. Box 7-D, Arica 1000007, Chile; (A.C.); (L.G.)
| | - Aylin Chong
- Organic and Polymeric Materials Research Laboratory, Facultad de Ciencias, Universidad de Tarapacá, P.O. Box 7-D, Arica 1000007, Chile; (A.C.); (L.G.)
| | - Linda Graffo
- Organic and Polymeric Materials Research Laboratory, Facultad de Ciencias, Universidad de Tarapacá, P.O. Box 7-D, Arica 1000007, Chile; (A.C.); (L.G.)
| | - María B. Camarada
- Centro de Nanotecnología Aplicada, Facultad de Ciencias, Universidad Mayor, Santiago 8580745, Chile;
- Núcleo de Química y Bioquímica, Facultad de Estudios Interdisciplinarios, Universidad Mayor, Santiago 8580745, Chile
| | - Catalina Espinoza
- Departamento de Química Inorgánica, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile; (C.E.); (F.A.A.)
| | - Felipe A. Angel
- Departamento de Química Inorgánica, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile; (C.E.); (F.A.A.)
- Centro de Nanotecnología y Materiales Avanzados, CIEN-UC, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
| | - Cesar Saldías
- Departamento de Química Física, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile;
| | - Alain Tundidor-Camba
- Research Laboratory for Organic Polymers (RLOP), Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile; (A.T.-C.); (C.A.T.)
- UC Energy Research Center, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
| | - Claudio A. Terraza
- Research Laboratory for Organic Polymers (RLOP), Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile; (A.T.-C.); (C.A.T.)
- UC Energy Research Center, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
| |
Collapse
|