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Continuous pin-hole free FA0.78Cs0.22Pb(I0.85Br0.15)3 flms are deposited by gas-assisted slot-die printing under ambient conditions using DMF/DMSO based ink containing Formamdinium Acetate additive. Using a binary solvent mixture of DMF and DMSO is effective in eliminating the non-perovskite phase that occurs when DMF alone is used. Print-speed, gas fow rate and chuck temperature are optimized to realize homogeneous flms with constant bandgap (1.63 eV) over large substrates (2″×4″). The perovskite flms prepared using two solvents DMF and DMF: DMSO (9:1) were incorporated in single junction devices. The resulting devices show improved fll factor with improved power conversion effciency. 

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. 

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. 

Hybrid halide perovskite solar cells have drawn widespread attention with the achievement of high power conversion efficiencies. However, poor stability remains the greatest barrier preventing their commercialization. Performance degradation and recovery have a complicated dependence on the environment and a dependence on the applied bias, which affects ion migration. Herein, solar cells with an organic hole transport layer and cells with an inorganic hole transport layer are compared. A type of degradation of the organic transport layer is examined, which is reversible by applying a forward bias soak, and how the degradation arises from ion migration mechanisms is explained. Experimental current–voltage and capacitance transient measurements are conducted as a function of temperature. The resulting S‐kink and positive capacitance decay are explained in terms of the modeled effects of a changing ion density at the hole transport layer. An irreversible degradation is found upon heating to more than 100 °C. On the contrary, the inorganic hole transport layer is found to eliminate the observable effects of ion migration, even at elevated temperatures, so long as air exposure is avoided.