TODAY at 4:30 PM
The Center for Excitonics/Perovskite Seminar Series
presents<http://www.rle.mit.edu/excitonics>cs>:
Predicting the Microstructure Stability in Photovoltaic Polymer-Fullerene Blends Using
Figure of
Merit*<http://www.rle.mit.edu/excitonics/events/predicting-the-microstru…
November 1, 2017 at 4:30pm/rm: 35-520
Jose Dario Perea
Friedrich Alexander Universität (Germany), Engineering, Visiting Student in the
Aspuru-Guzik Group at Harvard
[
http://www.rle.mit.edu/excitonics/wp-content/uploads/2017/10/perea_jd-240x3…]
A theoretical understanding of the micro-structure of organic semiconducting polymers and
blends is vital to further advance the optoelectronic device performance of organic
electronics. We outline the theoretical framework of a combined numerical approach based
on polymeric solution theory to study the microstructure of polymer-small-molecule blends.
We feed the results of ab initio density functional theory quantum chemistry calculations
into an artificial neural network for the determination of solubility parameters. These
solubility parameters are used to calculate Flory−Huggings intermolecular parameters. We
further show that the theoretical values are in line with experimentally determined data.
On the basis of the Flory−Huggings parameters, we establish a figure of merit as a
relative metric for assessing the phase diagrams of organic semiconducting blends in thin
films. This is demonstrated for polymer-fullerene blend films on the basis of the
prototypical polymers poly(3-hexylthiophene-2,5-diyl) (P3HT) and
poly[(5,6-difluoro-2,1,3-benzothiadiazol-4,7-diyl)-alt-(3,3-di(2-octyldodecyl)-2,2,5,2;5,2-quaterthiophen-5,5-diyl)]
(PffBT4T-2OD). After confirming the applicability of our model with a broader range of
materials and differences in molecular weight, we suggest that this combined model should
be able to inform design criteria and processing guidelines for existing and new high
performance semiconducting blends for organic electronics applications with ideal and
stable solid state morphology.
Jose Dario Perea is third-year PhD student of Engineering at Friedrich Alexander
Universität (Germany) and currently a visiting student at Harvard University, Department
of Chemistry and Chemical Biology working in Aspuru-Guzik´s group. Perea’s research
focuses on the determination of thermodynamic, electric and dynamic properties based in
different theoretical models for the improvement and understanding of the organic solar
cells. He has collaborated with research groups in several universities including the Max
Plank Institute of Colloids and Interfaces (Germany), Pannonia University (Hungary), and
Harvard University. He is co-organizer of an international conference on Next Generation
Solar Energy, to be held in Dec, 2017 in Cali – Colombia
(
www.ngse.info<http://www.ngse.info/>)/>). He has published in several journals,
including Nature Comm. and an author chapter book by Wiley.
Light refreshments will be served.
*This talk is part of the Perovskites Seminar Series organized by Juan-Pablo Correa-Baena
from MIT’s PV Lab and sponsored by the Center for Excitonics. For more info contact
Juan-Pablo: jpcorrea@mit.edu<mailto:jpcorrea@mit.edu>
The Center For Excitonics Is An Energy Frontier Research Center Funded By The U.S.
Department Of Energy,
Office Of Science And Office Of Basic Energy Sciences