TY - JOUR
T1 - Thin Films and Solar Cells Based on Semiconducting Two-Dimensional Ruddlesden-Popper (CH3(CH2)3NH3)2(CH3NH3)n-1SnnI3n+1 Perovskites
AU - Cao, Duyen H.
AU - Stoumpos, Konstantinos
AU - Yokoyama, Takamichi
AU - Logsdon, Jenna L.
AU - Song, Tze Bin
AU - Farha, Omar K.
AU - Wasielewski, Michael R.
AU - Hupp, Joseph T.
AU - Kanatzidis, Mercouri G.
N1 - Funding Information:
D.H.C. acknowledges support from the Link Foundation through the Link Foundation Energy Fellowship Program. T.-B.S. acknowledges financial support from Mitsubishi Chemical Group Science & Technology Research Center, Inc. This work 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, under Award Number DE-SC0001059. This work made use of the EPIC and Keck-II facilities of Northwestern University’s NUANCE Center, which has received support from the Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource (NSF NNCI-1542205); the MRSEC program (NSF DMR-1121262) at the Materials Research Center; the International Institute for Nanotechnology (IIN); the Keck Foundation; and the State of Illinois, through the IIN. D.H.C and J.L.L thank Dr. Lin Ma for her assistance with the photoluminescence measurement.
Publisher Copyright:
© 2017 American Chemical Society.
PY - 2017/5/12
Y1 - 2017/5/12
N2 - Low electrical resistivity (high dark carrier concentration) of CH3NH3SnI3 often leads to short-circuiting in solar cells, and appropriate thin-film modifications are required to ensure functional devices. The long-term durability of organic-inorganic perovskite solar cells necessitates the protection of perovskite thin films from moisture to prevent material decomposition. Herein, we report that the electrical resistivity and the moisture stability of two-dimensional (2D) Ruddlesden-Popper (CH3(CH2)3NH3)2(CH3NH3)n-1SnnI3n+1 perovskites are considerably improved compared to those of the three-dimensional (3D) CH3NH3SnI3 perovskite and subsequently show the solar cell fabrication using a simple one-step spin-coating method. These 2D perovskites are semiconductors with optical band gaps progressively decreasing from 1.83 eV (n = 1) to 1.20 eV (n = ). The n = 3 and n = 4 members with optimal band gaps of 1.50 and 1.42 eV for solar cells, respectively, were thus chosen for in-depth studies. We demonstrate that thin films of 2D perovskites orient the {(CH3NH3)n-1SnnI3n+1}2- slabs parallel to the substrate when dimethyl sulfoxide solvent is used for deposition, and this orientation can be flipped to perpendicular when N,N-dimethylformamide solvent is used. We find that high-purity, single-phase films can be grown only by using precursor solutions of "pre-synthesized" single-phase bulk perovskite materials. We introduce for the first time the use of triethylphosphine as an effective antioxidant, which suppresses the doping level of the 2D films and improves film morphology. The resulting semiconducting 2D Sn-based iodide perovskite films were incorporated in solar cells yielding a power conversion efficiency of 2.5% from the Sn4I13 member. From the temporal stability standpoint, the 2D Sn perovskite solar cells outperform their 3D analogs.
AB - Low electrical resistivity (high dark carrier concentration) of CH3NH3SnI3 often leads to short-circuiting in solar cells, and appropriate thin-film modifications are required to ensure functional devices. The long-term durability of organic-inorganic perovskite solar cells necessitates the protection of perovskite thin films from moisture to prevent material decomposition. Herein, we report that the electrical resistivity and the moisture stability of two-dimensional (2D) Ruddlesden-Popper (CH3(CH2)3NH3)2(CH3NH3)n-1SnnI3n+1 perovskites are considerably improved compared to those of the three-dimensional (3D) CH3NH3SnI3 perovskite and subsequently show the solar cell fabrication using a simple one-step spin-coating method. These 2D perovskites are semiconductors with optical band gaps progressively decreasing from 1.83 eV (n = 1) to 1.20 eV (n = ). The n = 3 and n = 4 members with optimal band gaps of 1.50 and 1.42 eV for solar cells, respectively, were thus chosen for in-depth studies. We demonstrate that thin films of 2D perovskites orient the {(CH3NH3)n-1SnnI3n+1}2- slabs parallel to the substrate when dimethyl sulfoxide solvent is used for deposition, and this orientation can be flipped to perpendicular when N,N-dimethylformamide solvent is used. We find that high-purity, single-phase films can be grown only by using precursor solutions of "pre-synthesized" single-phase bulk perovskite materials. We introduce for the first time the use of triethylphosphine as an effective antioxidant, which suppresses the doping level of the 2D films and improves film morphology. The resulting semiconducting 2D Sn-based iodide perovskite films were incorporated in solar cells yielding a power conversion efficiency of 2.5% from the Sn4I13 member. From the temporal stability standpoint, the 2D Sn perovskite solar cells outperform their 3D analogs.
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U2 - 10.1021/acsenergylett.7b00202
DO - 10.1021/acsenergylett.7b00202
M3 - Article
AN - SCOPUS:85021823998
VL - 2
SP - 982
EP - 990
JO - ACS Energy Letters
JF - ACS Energy Letters
SN - 2380-8195
IS - 5
ER -