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VERSION:2.0
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PRODID:UW-Madison-Physics-Events
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SEQUENCE:0
UID:UW-Physics-Event-2044
DTSTART:20110428T150000Z
DURATION:PT1H0M0S
DTSTAMP:20260418T235648Z
LAST-MODIFIED:20110419T140757Z
LOCATION:5310 Chamberlin
SUMMARY:Improved Charge Collection in Nanostructured Organic Semicondu
 ctor Solar Cells\, R. G. Herb Condensed Matter Seminar\, Charles Black
 \, Brookhaven National Lab
DESCRIPTION:High-performance organic semiconductor solar cell active l
 ayers form via a self-assembly process of phase separation of blended 
 donor and acceptor materials.  Achieving optimal device performance re
 quires a delicate balance of trapping the blended material in a non-eq
 uilibrium configuration.  I will describe our experimental efforts to 
 confine both organic semiconductors and semiconductor blends within na
 nometer-scale volumes to better control material phase separation and 
 understand the effect of geometry on the material structure\, its elec
 tronic properties\, and its photovoltaic performance.  <br>
\n<br>
\nA
 s one example\, confining blended poly(3-hexylthiophene): [6\,6]-pheny
 l-C61-butyric acid methyl ester organic solar cell active layers withi
 n nanometer-scale cylindrical volumes more than doubles the supported 
 photocurrent density compared to equivalent unconfined volumes of the 
 same blend\, and increases the poly(3-hexylthiophene) hole mobility in
  the blend by more than 500 times. Grazing incidence x-ray diffraction
  measurements show that the confining volume disrupts polymer ordering
  by reducing crystallinity and grain size\, as well as changing crysta
 l orientation.
URL:https://www.physics.wisc.edu/events/?id=2044
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