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Title: Directional Charge Separation in Isolated Organic Semiconductor Crystalline Nanowires

Abstract

In the conventional view of organic photovoltaics (OPV), localized electronic excitations (excitons) formed in the active layer are transported by random 3D diffusion to an interface where charge separation and extraction take place. Because radiative de-excitation is usually strongly allowed in organic semiconductors, efficient charge separation requires high exciton mobility, with much of the diffusive motion ‘wasted’ in directions that don’t result in an interface encounter. Our research efforts are focused on ways to enforce a preferred directionality in energy and/or charge transport using ordered crystalline nanowires in which the intermolecular interactions that facilitate transport along, for example, the pi-stacking axis, can be made several orders of magnitude stronger than those in a transverse direction. The results presented in our recent work (Nature Communications) is a first step towards realizing the goal of directional control of both energy transport and charge separation, where excitons shared between adjacent molecules dissociate exclusively along the pi-stacking direction.

Authors:
; ; ; ;
Publication Date:
Research Org.:
University of Massachusetts Amherst
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Chemical Sciences, Geosciences & Biosciences Division
OSTI Identifier:
1429404
Report Number(s):
Natue Communications DOI: 10.1038/ ncomms10629
DOE Contract Number:
FG02-05ER15695
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
nanowire, organic semiconductor, directional charge separation

Citation Formats

Barnes, Michael, Labastide, Joelle, Bond-Thompson, Hilary, Briseno, Alejandro, and Collela, Nicolas. Directional Charge Separation in Isolated Organic Semiconductor Crystalline Nanowires. United States: N. p., 2017. Web. doi:10.2172/1429404.
Barnes, Michael, Labastide, Joelle, Bond-Thompson, Hilary, Briseno, Alejandro, & Collela, Nicolas. Directional Charge Separation in Isolated Organic Semiconductor Crystalline Nanowires. United States. doi:10.2172/1429404.
Barnes, Michael, Labastide, Joelle, Bond-Thompson, Hilary, Briseno, Alejandro, and Collela, Nicolas. Wed . "Directional Charge Separation in Isolated Organic Semiconductor Crystalline Nanowires". United States. doi:10.2172/1429404. https://www.osti.gov/servlets/purl/1429404.
@article{osti_1429404,
title = {Directional Charge Separation in Isolated Organic Semiconductor Crystalline Nanowires},
author = {Barnes, Michael and Labastide, Joelle and Bond-Thompson, Hilary and Briseno, Alejandro and Collela, Nicolas},
abstractNote = {In the conventional view of organic photovoltaics (OPV), localized electronic excitations (excitons) formed in the active layer are transported by random 3D diffusion to an interface where charge separation and extraction take place. Because radiative de-excitation is usually strongly allowed in organic semiconductors, efficient charge separation requires high exciton mobility, with much of the diffusive motion ‘wasted’ in directions that don’t result in an interface encounter. Our research efforts are focused on ways to enforce a preferred directionality in energy and/or charge transport using ordered crystalline nanowires in which the intermolecular interactions that facilitate transport along, for example, the pi-stacking axis, can be made several orders of magnitude stronger than those in a transverse direction. The results presented in our recent work (Nature Communications) is a first step towards realizing the goal of directional control of both energy transport and charge separation, where excitons shared between adjacent molecules dissociate exclusively along the pi-stacking direction.},
doi = {10.2172/1429404},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Mar 01 00:00:00 EST 2017},
month = {Wed Mar 01 00:00:00 EST 2017}
}

Technical Report:

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