Excited-State Photophysics in a Low Band Gap Polymer with High Photovoltaic Efficiency
العنوان: | Excited-State Photophysics in a Low Band Gap Polymer with High Photovoltaic Efficiency |
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المؤلفون: | Andrew M. Moran, Andrew C. Stuart, Huaxing Zhou, Wei You, Jordan M. Womick, Stephen A. Miller |
المصدر: | The Journal of Physical Chemistry C. 115:2371-2380 |
بيانات النشر: | American Chemical Society (ACS), 2010. |
سنة النشر: | 2010 |
مصطلحات موضوعية: | Materials science, Organic solar cell, Band gap, Charge density, Electronic structure, Photochemistry, Molecular physics, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Photoexcitation, General Energy, Excited state, Femtosecond, Physical and Theoretical Chemistry, Absorption (electromagnetic radiation) |
الوصف: | We report an experimental investigation of a newly synthesized polymer, PNDT-DTPyT, with a 1.55 eV band gap tuned for optimal photovoltaic performance. Several time-resolved optical spectroscopies are used to examine fundamental photophysics in pure polymer films. Clear signatures of a distribution in photoexcitation sizes are found in steady state absorption and fluorescence measurements conducted from 100 to 300 K. Electronic structure calculations are combined with an empirical model to establish that, on average, the excitations span less than two repeat units because of strong interactions with the surrounding environment. These strong vibronic interactions are attributed to the charge transfer nature of the excitation, which involves a significant change in the spatial charge distribution. Femtosecond transient grating (TG) measurements find energy transfer processes occurring with roughly 1 and 10 ps time constants. This distinction in time scales most likely has a geometric origin (e.g., processes... |
تدمد: | 1932-7455 1932-7447 |
URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_________::94dc175c434072e9ef4ee7f5b47a1470 https://doi.org/10.1021/jp108534d |
رقم الأكسشن: | edsair.doi...........94dc175c434072e9ef4ee7f5b47a1470 |
قاعدة البيانات: | OpenAIRE |
تدمد: | 19327455 19327447 |
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