To start the crystallization of the tin (Sn) based
perovskite materials, anti-solvent treatment is a useful technique.
But the use of anti-solvents increases the complexity of the
deposition process thus hinders the applicability in mass
production processes. Here we have developed an anti-solvent
free MAPb0.75Sn0.25(I0.50Br0.50)3 perovskite thin film deposition
method based on a one step spin coating process. Addition of 0 -
100 mol% of methylammonium acetate (MAAc) to the precursor
ink allows for the deposition of continuous films. Films casted
from ink with less than 60 mol% MAAc show pinholes and are
rough. A decent crystalline and pin-hole free perovskite thin film
can be obtained from 60 or more mol% MAAc additive. These
results are confirmed by XRD, AFM and SEM measurements.
MAPb0.75Sn0.25(I0.50Br0.50)3 has a wide bandgap and is currently
being considered for applications in tandem solar cells and under
water solar cells.
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Fabricate anti-solvent free tin-lead based perovskite solar cells with MAAc additives
Anti-solvent-free one-step deposition of perovskite thin film shows promising potential for application in slot-die or roll-to-roll mass fabrication processes of perovskite solar cells. The continuous coverage was confirmed by PV response of devices made using the on-step deposition process. In this work, we have developed a process to deposit MAPB0.75Sn0.25(I0.5Br0.5)3 perovskite thin films without anti-solvent adding MAAc to the ink. By varying the Br content of the perovskite precursor, we were able to tune the bandpap. Fabricated solar cells with the structure ITO/CuI/MAPb0.75Sn0.25(I0.5Br0.5)3/C60/BCP/Al with PCE of 4.59% show the parth of the fabrication process of antisolvent-free tin-lead-based solar cells.
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- Award ID(s):
- 1906492
- NSF-PAR ID:
- 10461788
- Editor(s):
- Li, Gang; Nguyen, Thuc-Quyen; Nogueira, Ana Flávia; Rand, Barry P.; Moons, Ellen; Stingelin, Natalie
- Date Published:
- Journal Name:
- Organic, Hybrid, and Perovskite Photovoltaics XXIII, 1220905
- Volume:
- 12209
- Page Range / eLocation ID:
- 53
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Triple cation Cs/methylammonium (MA)/formamidinium (FA) and double halide Br/I lead perovskites improved the stability and efficiency of perovskite solar cells (PVSCs). However, their effects on alloyed Pb–Sn perovskites are unexplored. In this work, perovskite thin films with the composition Cs x (MA 0.17 FA 0.83 ) 1−x Pb 1−y Sn y (I 0.83 Br 0.17 ) 3 are synthesized utilizing a one-step solution process plus an anti-solvent wash technique and deployed in PVSCs with an inverted architecture. All films show a cubic crystal structure, demonstrating that compositional tuning of both the tolerance factor and crystallization rate allows for dense, single phase formation. The band gaps, affected by both lattice constriction and octahedral tilting, show opposite trends in Pb-rich or Sn-rich perovskites with the increase of Cs for fixed Sn compositions. The Cs 0.05 (MA 0.17 FA 0.83 ) 0.95 Pb 0.25 Sn 0.75 (I 0.83 Br 0.17 ) 3 PVSCs achieve a power conversion efficiency (PCE) of 11.05%, a record for any PVSC containing 75% Sn perovskites, and the Cs 0.10 (MA 0.17 FA 0.83 ) 0.90 Pb 0.75 Sn 0.25 (I 0.83 Br 0.17 ) 3 PVSCs reach a record PCE of 15.78%. Moreover, the triple cation and double halide alloyed Pb–Sn perovskites exhibit improved device stability under inert and ambient conditions. This study, which illustrates the impact of cation and halide tuning on alloyed Pb–Sn perovskites, can be used to further eliminate Pb and improve device performance of high Sn PVSCs and other optoelectronic devices.more » « less
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1117/12.2634371
