TY - JOUR
T1 - Effects of X-rays on Perovskite Solar Cells
AU - Stuckelberger, Michael E.
AU - Nietzold, Tara
AU - West, Bradley M.
AU - Luo, Yanqi
AU - Li, Xueying
AU - Werner, Jérémie
AU - Niesen, Björn
AU - Ballif, Christophe
AU - Rose, Volker
AU - Fenning, David P.
AU - Bertoni, Mariana I.
N1 - Publisher Copyright:
Copyright © 2020 American Chemical Society.
PY - 2020/8/20
Y1 - 2020/8/20
N2 - Synchrotron micro- and nanoprobe beamlines have demonstrated great potential to advance photovoltaic devices. Most importantly, their small X-ray spot size has enabled the direct correlation of electrical performance with elemental composition at subgrain resolution for a variety of polycrystalline solar cells. Whereas the bulk of most inorganic semiconductors is stable under the high X-ray flux of focused X-ray beams, semiconductors with organic components are prone to a variety of degradation mechanisms. This is particularly critical to evaluate for the emerging organometal halide perovskite solar cells. Here, we investigate the effects of hard X-rays on the nanoscale performance and elemental distribution of these solar cells. We show that their composition does not change during common operando and in situ measurements at synchrotron nanoprobes. However, we found a significant X-ray-induced electronic degradation of solar cells with methylammonium lead iodide absorbers. Time- and dose-dependent measurements unveiled two characteristic degradation time constants on the order of 12 and 200 s that are independent of the X-ray flux. On the basis of heat and dose simulations, we attribute the fast decay to the dose-driven creation of recombination centers, while the slow decay is compatible with the observation of compositional changes. Finally, we detail how degradation-induced measurement artifacts can be outrun and showcase the high correlation of the X-ray-beam-induced current with the iodine and lead distribution.
AB - Synchrotron micro- and nanoprobe beamlines have demonstrated great potential to advance photovoltaic devices. Most importantly, their small X-ray spot size has enabled the direct correlation of electrical performance with elemental composition at subgrain resolution for a variety of polycrystalline solar cells. Whereas the bulk of most inorganic semiconductors is stable under the high X-ray flux of focused X-ray beams, semiconductors with organic components are prone to a variety of degradation mechanisms. This is particularly critical to evaluate for the emerging organometal halide perovskite solar cells. Here, we investigate the effects of hard X-rays on the nanoscale performance and elemental distribution of these solar cells. We show that their composition does not change during common operando and in situ measurements at synchrotron nanoprobes. However, we found a significant X-ray-induced electronic degradation of solar cells with methylammonium lead iodide absorbers. Time- and dose-dependent measurements unveiled two characteristic degradation time constants on the order of 12 and 200 s that are independent of the X-ray flux. On the basis of heat and dose simulations, we attribute the fast decay to the dose-driven creation of recombination centers, while the slow decay is compatible with the observation of compositional changes. Finally, we detail how degradation-induced measurement artifacts can be outrun and showcase the high correlation of the X-ray-beam-induced current with the iodine and lead distribution.
UR - http://www.scopus.com/inward/record.url?scp=85091849151&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85091849151&partnerID=8YFLogxK
U2 - 10.1021/acs.jpcc.0c04645
DO - 10.1021/acs.jpcc.0c04645
M3 - Article
AN - SCOPUS:85091849151
SN - 1932-7447
VL - 124
SP - 17949
EP - 17956
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
IS - 33
ER -