Suppressed Ion Migration in Low-Dimensional Perovskites

Abstract

Ion migration, which occurs in regular three-dimensional perovskites, is shown to be suppressed in low-dimensional perovskites both in the dark and under illumination, an indication of better stability of these materials for solar cells and light-emitting diodes.

Mixed 3D–2D Passivation Treatment for Mixed‐Cation Lead Mixed‐Halide Perovskite Solar Cells for Higher Efficiency and Better Stability

“…Energy Mater. [32,35] This is supported by the results of recent study showing that ionic migration behavior in 3D perovskites has been dramatically reduced in 2D and quasi-2D layered perovskite phases [37] present in the MP layers here. It is likely that in the presence of bulky iBA + an energetic barrier could have been formed that somewhat suppresses the halide-related defect migration.…”

“…The effect of scan speed on photocurrent hysteresis in the devices was also investigated (Figure 6b). With regards to the latter, it has been recently demonstrated that ionic transport can be efficiently suppressed in layered (BA) 2 (MA) 3 Pb 4 I 13 (n = 4) perovskites, [37] consistent with low-dimensional quasi-2D phases grown within MP50, MP75, and MP100 layers. On the other hand, hysteresis in MP50-treated cells was significantly suppressed, even at fast scan rates.…”

Management of Crystallization Kinetics for Efficient and Stable Low‐Dimensional Ruddlesden–Popper (LDRP) Lead‐Free Perovskite Solar Cells

“…The LDRP perovskites exhibited low selfdoping effect, suppressed ion migration, and excellent oriented growth over 3D perovskite due to this multiple-quantum-well structure, [27][28][29][30] which is benefit to inhibit the defect density in Sn perovskites. Most importantly, the organic amine molecules can be self-assembled with perovskite sheets through hydrogen bond so resulting in the quantum well structure with quantum confinement effect, which improve the thermodynamic stability and hydrophobic of lead-free perovskite.…”

“…The layer number of LDRP Sn perovskite was fixed at n = 4, that is, BA 2 MA 3 Sn 4 I 13 . [3] We proposed that this may be attributed to the introduction of BA cation which also has the effect of retarding the crystallization of perovskite, [28,29,32] resulting in the excessive retardation of reaction between SnI 2 and MACl and thus the poor surface coverage. As shown in Figure 1a, we clearly observed that the LDRP BA 2 MA 3 Sn 4 I 13 perovskite films from DMSO (Lewis theory) have poor surface coverage, which is different from previous work demonstrating that the intermediate phase 3DMSO-SnI 2 formed by the Lewis base DMSO and SnI 2 can retard the rapid reaction between SnI 2 and MACl and achieve the high-quality perovskite films.…”

Two-dimensional organic-inorganic hybrid perovskite: from material properties to device applications

“…The ion conductivity and ion migration activation energy both in the dark and under illumination were measured by Lin et al [50] to investigate the ion migration stability in these materials. Under illumination, the conductivity should be mainly attributed to the photogenerated carriers.…”