Effects of electron-withdrawing group and electron-donating core combinations on physical properties and photovoltaic performance in D-π-A star-shaped small molecules |
| |
| Affiliation: | 1. Enikolopov Institute of Synthetic Polymeric Materials of the Russian Academy of Sciences, Profsoyuznaya st. 70, Moscow, 117393, Russia;2. Institute of Materials for Electronics and Energy Technology (i-MEET), Friedrich-Alexander-University Erlangen-Nuremberg, Martensstraße 7, 91058, Erlangen, Germany;3. Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands;4. Faculty of Physics & International Laser Center, Lomonosov Moscow State University, Leninskie Gory 1, 119991, Moscow, Russia;5. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova St. 28, Moscow, 119991, Russia;6. National Research Centre “Kurchatov Institute”, 1, Akademika Kurchatova pl., Moscow, 123182, Russia;7. Bavarian Center for Applied Energy Research (ZAE Bayern), Haberstraße 2a, 91058, Erlangen, Germany;8. Chemistry Department, Moscow State University, Leninskie Gory 1-3, Moscow, 119991, Russia;1. Equipe d’Electrochimie et Environnement, Faculté des Sciences et Techniques, Université Moulay Ismaîl, Errachidia, Morocco;2. Regional Center for Education and Training Professions, BP: 8, Errachidia, Morocco;3. Bitlis Eren University, Faculty of Arts and Science, Department of Physics, 13000 Bitlis, Turkey;4. Molecular Chemistry and Natural Substances Laboratory, Faculty of Science, University Moulay Ismail, Meknes, Morocco;1. Faculty of Chemistry, University of Warsaw, ul. Pasteura 1, 02-093 Warsaw, Poland;2. Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, ul. Niezapominajek 8, 30-239 Cracow, Poland |
| |
| Abstract: | The first representatives of star-shaped molecules having 3-alkylrhodanine (alkyl-Rh) electron-withdrawing groups, linked through bithiophene π-spacer with electron-donating either triphenylamine (TPA) or tris(2-methoxyphenyl)amine (m-TPA) core were synthesized. The physical properties and photovoltaic performance of these novel molecules with 3-ethylrhodanine groups were comprehensively studied and compared to their full analogs having dicyanovinyl (DCV) units as the other type of well-known and frequently used acceptor groups. On one hand, the former demonstrate several advantages such as higher solubility and better photovoltaic performance in bulk-heterojunction (BHJ) organics solar cells (OSCs) as compared to the latter. Nevertheless, the former have slightly lower optical/electrochemical bandgaps and higher thermooxidation stability. On the other hand, molecules of both series based on m-TPA core along with higher solubility and higher position of HOMO energy levels have more pronounced tendency to crystalize as compared to the TPA-based molecules. Detailed investigation of the structure-property relationships for these series of molecules revealed that donor and acceptor unit combinations influence both charge generation and charge transport/recombination properties, as demonstrated by the ultrafast photoinduced absorption spectroscopy, space charge limited current measurements and transient photovoltage technique. These results give more insight how to fine-tune and predict physical properties and photovoltaic performance of small molecules having either alkyl-Rh or DCV units in their chemical structures and thus providing a molecular design guideline for the next generation of high-performance photovoltaic materials. |
| |
| Keywords: | Star-shaped molecules 3-Ethylrhodanine Triphenylamine Dicyanovinyl Organic solar cells Ultrafast charge separation |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
