Please use this identifier to cite or link to this item: https://doi.org/10.1021/jp310841v
Title: On the origin of the quadrant I semicircle in intensity-modulated photocurrent spectra of P3HT:PCBM Bulk heterojunction solar cells: Evidence of degradation-related trap-assisted recombination
Authors: Set, Y.T.
Heinemann, M.D.
Birgersson, E. 
Luther, J. 
Issue Date: 25-Apr-2013
Source: Set, Y.T., Heinemann, M.D., Birgersson, E., Luther, J. (2013-04-25). On the origin of the quadrant I semicircle in intensity-modulated photocurrent spectra of P3HT:PCBM Bulk heterojunction solar cells: Evidence of degradation-related trap-assisted recombination. Journal of Physical Chemistry C 117 (16) : 7993-8000. ScholarBank@NUS Repository. https://doi.org/10.1021/jp310841v
Abstract: Intensity-modulated photocurrent spectroscopy (IMPS) characterizes the charge carrier transport in a solar cell by subjecting it to a sinusoidally varying illumination and measuring the resultant photocurrent. The IMPS spectra of certain P3HT:PCBM bulk heterojunction solar cells exhibit a poorly understood feature: A quadrant I semicircle, which implies that the sinusoidal variation of the photocurrent leads that of the illumination in a certain frequency range. To understand the mechanisms underlying this feature, we have adopted a mathematical framework based on drift-diffusion modeling instead of the conventional equivalent circuit approach. By incorporating the effects of traps into the mathematical model and conducting targeted experiments, we have demonstrated that the quadrant I semicircle arises from degradation-related trap states behaving as recombination centers. Our analysis of the device's intrinsic mechanisms indicates that the trap-assisted recombination can have a time scale that is at least one order of magnitude slower than that of the carrier extraction mechanism; such a mismatch can generate the observed quadrant I semicircle. © 2013 American Chemical Society.
Source Title: Journal of Physical Chemistry C
URI: http://scholarbank.nus.edu.sg/handle/10635/64324
ISSN: 19327447
DOI: 10.1021/jp310841v
Appears in Collections:Staff Publications

Show full item record
Files in This Item:
There are no files associated with this item.

SCOPUSTM   
Citations

12
checked on Dec 13, 2017

WEB OF SCIENCETM
Citations

12
checked on Nov 16, 2017

Page view(s)

33
checked on Dec 16, 2017

Google ScholarTM

Check

Altmetric


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.