TY - JOUR
T1 - Impact of microstructure on the electron-hole interaction in lead halide perovskites
AU - Mahboubi Soufiani, Arman
AU - Yang, Zhuo
AU - Young, Trevor
AU - Miyata, Atsuhiko
AU - Surrente, Alessandro
AU - Pascoe, Alexander
AU - Galkowski, Krzysztof
AU - Abdi-Jalebi, Mojtaba
AU - Brenes, Roberto
AU - Urban, Joanna
AU - Zhang, Nan
AU - Bulović, Vladimir
AU - Portugall, Oliver
AU - Cheng, Yi-Bing
AU - Nicholas, Robin J.
AU - Ho-Baillie, Anita
AU - Green, Martin A.
AU - Plochocka, Paulina
AU - Stranks, Samuel D.
PY - 2017/6/1
Y1 - 2017/6/1
N2 - Despite the remarkable progress in the performance of devices based on the lead halide perovskite semiconductor family, there is still a lack of consensus on their fundamental photophysical properties. Here, using magneto-optical transmission spectroscopy we elucidate the impact of the microstructure on the Coulomb interaction between photo-created electron-hole pairs in methylammonium lead triiodide (MAPbI3) and the triple-cation lead mixed-halide composition, Cs0.05(MA0.17FA0.83)0.95Pb(I0.83Br0.17)3 (Cs: cesium, MA: methylammonium, FA: formamidinium) by investigating thin films with a wide range of grain sizes from tens of nanometers to microns. At low temperatures, in which thermal fluctuations of the interactions are frozen and the rotational disorder of the organic cation is negligible, the exciton binding energy and reduced effective mass of carriers remain effectively unchanged with grain size. We conclude that the microstructure plays a negligible role in the Coulomb interaction of the photo-created electron-hole pairs, in contrast to previous reports. This renewed understanding of the relationship between these fundamental electronic properties and the microstructure is critical for future fundamental studies and improving device design.
AB - Despite the remarkable progress in the performance of devices based on the lead halide perovskite semiconductor family, there is still a lack of consensus on their fundamental photophysical properties. Here, using magneto-optical transmission spectroscopy we elucidate the impact of the microstructure on the Coulomb interaction between photo-created electron-hole pairs in methylammonium lead triiodide (MAPbI3) and the triple-cation lead mixed-halide composition, Cs0.05(MA0.17FA0.83)0.95Pb(I0.83Br0.17)3 (Cs: cesium, MA: methylammonium, FA: formamidinium) by investigating thin films with a wide range of grain sizes from tens of nanometers to microns. At low temperatures, in which thermal fluctuations of the interactions are frozen and the rotational disorder of the organic cation is negligible, the exciton binding energy and reduced effective mass of carriers remain effectively unchanged with grain size. We conclude that the microstructure plays a negligible role in the Coulomb interaction of the photo-created electron-hole pairs, in contrast to previous reports. This renewed understanding of the relationship between these fundamental electronic properties and the microstructure is critical for future fundamental studies and improving device design.
UR - http://www.scopus.com/inward/record.url?scp=85021932777&partnerID=8YFLogxK
U2 - 10.1039/c7ee00685c
DO - 10.1039/c7ee00685c
M3 - Article
AN - SCOPUS:85021932777
SN - 1754-5692
VL - 10
SP - 1358
EP - 1366
JO - Energy & Environmental Science
JF - Energy & Environmental Science
IS - 6
ER -
