Mixed dimensionality of 2D/3D heterojunctions for improving charge transport and long-term stability in high-efficiency 1.63 eV bandgap perovskite solar cells

Abstract

By using R-α-MBA with bromine terminal to develop 2D perovskite with mixed dimensionality on the 3D perovskite surface, an improved PCE of 21.48% with a FF of 82.44 was achieved for 1.63 eV bandgap perovskite solar cells.

Energy Transfer-Dominated Quasi-2D Blue Perovskite Light-Emitting Diodes

“…This change by the strong quantum confinement effect may result from the two Br atoms on the DBA molecule reducing the formation energy of the low-dimensional phase and increasing the nucleation site or steric hindrance due to their stronger electronegativity. 18,47,48 The grain sizes of SFB-modified and DBA@SFB-modified perovskite films were calculated using the Scherrer equation from the XRD pattern to be approximately 220 and 130 nm, respectively (Figures 3b and S10), which is consistent with the observations of blue shifts. In addition to altering the phase distribution, there is also an enhanced PL intensity for the DBA@SFB-modified perovskite films.…”

Insights into the Cation Migration Kinetics across 2D/3D Perovskite Interfaces and Strategy for Its Prevention

“…11−13 Passivating these defect states reduces the nonradiative recombination, allowing for improved stability of the perovskite. 14,15 Another source of perovskite degradation is moisture, which can lead to destructive hydration of the perovskite phases and form a hydrated product, which decreases absorption across the visible range. 6 For instance, MAPbI 3 exhibits a deep black color in the αphase, but upon exposure to moisture, it changes into a yellow δ-phase.…”

“…The rapid enhancement in efficiency has been accelerated by their exciting optoelectronic properties, such as tunable bandgap, the high absorption coefficient, long charge carrier diffusion length, and their high carrier mobility . However, most 3D MHPs suffer from instability due to environmental factors like oxygen, moisture, thermal stresses, etc., which have slowed the commercialization of their PV devices. − The instability can occur because of intrinsic and extrinsic reasons such as interstitial and surface defects. , Most defects, such as undercoordinated bonds, vacancies, etc., are formed during the crystallization of the perovskite, and they behave as nonradiative recombination centers and affect the overall device stability. − Passivating these defect states reduces the nonradiative recombination, allowing for improved stability of the perovskite. , Another source of perovskite degradation is moisture, which can lead to destructive hydration of the perovskite phases and form a hydrated product, which decreases absorption across the visible range . For instance, MAPbI 3 exhibits a deep black color in the α-phase, but upon exposure to moisture, it changes into a yellow δ-phase. , Oxygen accelerates these undesired phase transformations in perovskites …”

Anisotropic Electron–Phonon Interactions in 2D Lead-Halide Perovskites

“…Despite outstanding characteristics, the instability of the halide perovskites in ambient environments has hindered its applicability. Since two-dimensional (2D) perovskites exhibit enhanced stability and enable improved performance of 2 D /3D heterostructures, − it would be ideal to systematically investigate potentially interesting optoelectronic properties arising from the confinement.…”