TY - JOUR
T1 - Carrier Diffusion Lengths of over 500 nm in Lead-Free Perovskite CH3NH3SnI3 Films
AU - Ma, Lin
AU - Hao, Feng
AU - Stoumpos, Konstantinos
AU - Phelan, Brian T.
AU - Wasielewski, Michael R.
AU - Kanatzidis, Mercouri G.
N1 - Funding Information:
This research was supported as part of the ANSER Center, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences (award no. DE-SC0001059), and ISEN at Northwestern University.
Publisher Copyright:
© 2016 American Chemical Society.
PY - 2016/11/9
Y1 - 2016/11/9
N2 - The dynamics of photoexcited lead-free perovskite films, CH3NH3SnI3, were studied using broadband transient absorption and time-resolved fluorescence spectroscopy. Similar to its lead analogue CH3NH3PbI3, we show that free carrier (electrons and holes) recombination is also the dominant relaxation pathway in CH3NH3SnI3 films. The slow hot carrier relaxation time is 0.5 ps. Long carrier diffusion lengths for electrons (279 ± 88 nm) and holes (193 ± 46 nm) were obtained from fluorescence quenching measurements. We also show that SnF2 doping in the CH3NH3SnI3 film effectively increases the fluorescence lifetime up to 10 times and gives diffusion lengths exceeding 500 nm. These results suggest that the photophysics of CH3NH3SnI3 perovskite are as favorable as those of CH3NH3PbI3, demonstrating that it is a promising nontoxic lead-free replacement for lead iodide perovskite-based solar cells.
AB - The dynamics of photoexcited lead-free perovskite films, CH3NH3SnI3, were studied using broadband transient absorption and time-resolved fluorescence spectroscopy. Similar to its lead analogue CH3NH3PbI3, we show that free carrier (electrons and holes) recombination is also the dominant relaxation pathway in CH3NH3SnI3 films. The slow hot carrier relaxation time is 0.5 ps. Long carrier diffusion lengths for electrons (279 ± 88 nm) and holes (193 ± 46 nm) were obtained from fluorescence quenching measurements. We also show that SnF2 doping in the CH3NH3SnI3 film effectively increases the fluorescence lifetime up to 10 times and gives diffusion lengths exceeding 500 nm. These results suggest that the photophysics of CH3NH3SnI3 perovskite are as favorable as those of CH3NH3PbI3, demonstrating that it is a promising nontoxic lead-free replacement for lead iodide perovskite-based solar cells.
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U2 - 10.1021/jacs.6b09257
DO - 10.1021/jacs.6b09257
M3 - Article
C2 - 27750426
AN - SCOPUS:84994528776
VL - 138
SP - 14750
EP - 14755
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
SN - 0002-7863
IS - 44
ER -