Oriented and Uniform Distribution of Dion–Jacobson Phase Perovskites Controlled by Quantum Well Barrier Thickness

Abstract

Dion–Jacobson (DJ) phase halide perovskites have attracted extensive attention in photovoltaic devices due to their significantly enhanced stability when compared with conventional 3D analogs. However, fundamental questions concerning the quantum well (QW) barrier thicknesses, which are critical to design efficient DJ phase perovskite photovoltaics, remain unknown. Herein, it is unambiguously demonstrated that QW barrier thickness, depending on bulky organic ammonium spacers with different chain lengths, such as 1.3‐propanediamine (PDA), 1.4‐butanediamine (BDA), 1.5‐pentamethylenediamine (PeDA), and 1.6‐hexamethylenediamine (HDA), allows the control of orientation and QW distribution. The DJ phase perovskites based on PDA and BDA have suitable QW barrier thicknesses, which exhibit excellent orientation and more uniform QW distribution, allowing a smooth bandgap transition that leads to longer carrier diffusion length, higher charge mobility, and lower defect density. Conversely, PeDA and HDA, with thicker QW barriers, result in lower orientation and multiple DJ perovskite phases. DJ phase perovskite photovoltaic devices based on PDA and BDA show significantly improved power conversion efficiencies (PCEs) of 14.16% and 16.38% compared with PCEs of 12.95% and 10.55% for PeDA and HDA analogs, respectively.

Formamidinium‐Based Dion‐Jacobson Layered Hybrid Perovskites: Structural Complexity and Optoelectronic Properties

“…), two main archetypes of layered perovskites are predominant to date, namely Ruddlesden-Popper (RP) and Dion-Jacobson (DJ) systems. [9][10][11][12][13][14][15][16][17][18][19][20] The RP structural category is defined by the S 2 A n-1 Pb n X 3n+1 formulation, which comprises an organic double layer between the inorganic layers featuring an offset per unit cell of the perovskite slab. [9][10][11][12] The DJ systems are based on the S'A n-1 Pb n X 3n+1 compositions employing organic layers (S') that stack in an almost perfect alignment between unit cells, featuring smaller interlayer space.…”

“…[9][10][11][12] The DJ systems are based on the S'A n-1 Pb n X 3n+1 compositions employing organic layers (S') that stack in an almost perfect alignment between unit cells, featuring smaller interlayer space. [15][16][17][18][19][20] Reducing interlayer distances and tuning their mutual alignment are important parameters for controlling the optoelectronic properties as they strengthen electronic interactions between the inorganic layers and, consequently, facilitate interlayer charge transport, rendering the DJ structures superior to RP phases. [15][16][17][18][19][20] Most of the developments of layered hybrid perovskites are based on RP archetypes and there are very few examples of hybrid DJ architectures to date.…”

“…[15][16][17][18][19][20] Reducing interlayer distances and tuning their mutual alignment are important parameters for controlling the optoelectronic properties as they strengthen electronic interactions between the inorganic layers and, consequently, facilitate interlayer charge transport, rendering the DJ structures superior to RP phases. [15][16][17][18][19][20] Most of the developments of layered hybrid perovskites are based on RP archetypes and there are very few examples of hybrid DJ architectures to date. [15][16][17][18][19][20] This is particularly the case for FA-containing layered perovskites, which are relatively unexplored despite the superior thermal stabilities of FA-based hybrid perovskite compositions.…”

Interlayer Cross‐Linked 2D Perovskite Solar Cell with Uniform Phase Distribution and Increased Exciton Coupling

“…After that, Ahmad et al reported a highly efficient 13.3% DJ phase PSCs with thousand hours ultrahigh stability using the same molecule. Zheng et al reported 16.38% efficiency DJ PSCs with MAAc molten salt as solvent; Li et al reported 14.86% efficiency for (BEA) 0.5 MA 3 Pb 3 I 10 DJ PSCs. Until recently, Cohen et aland Li et al reported a novel organic spacer 1,4‐phenylenedimethanammonium (PDMA) as novel DJ perovskite, yielding 15.6% and 7% separately.…”

Structural and Electronic Impact of an Asymmetric Organic Ligand in Diammonium Lead Iodide Perovskites

“…To improve upon the efficiency of these devices while preserving stability, the similar Dion–Jacobson phase perovskites (DJPs) have been of recent interest. [ 11–14 ] These materials have the typical chemical structure A'A n −1 Pb n X 3 n +1 , where n is the number of inorganic repeat layers sandwiched between the organic ligands, A' is an organic diammonium cation, A is an organic or inorganic cation, and X is a halide anion (I, Br). DJPs resemble RPPs in their structure of alternating organic and Pb‐halide layers, however they maintain several key differences.…”