Toward Phase Stability: Dion–Jacobson Layered Perovskite for Solar Cells

Abstract

Three-dimensional halide-based perovskites have emerged as promising semiconducting light harvesters for thin-film solar cell fabrication; however, their intrinsic instability under humidity restricts their potential commercialization. To address such challenges, the development of low-dimensional/layered Dion–Jacobson (DJ) phase perovskites has recently gained substantial attention due to their intriguing environmental stability and competitive power conversion efficiency. In this Review, we have screened and focused our investigation on the DJ phase in layered perovskites for solar cell fabrication, especially elucidation of the active role played by organic spacer cations. We also discuss the possible strategies that can be employed to further push the performance of DJ-based perovskite solar cells.

Spacer Cation Tuning Enables Vertically Oriented and Graded Quasi‐2D Perovskites for Efficient Solar Cells

“…The crystal structures of the Q‐2D RP layered perovskites, (PEA) 2 MA 3 Pb 4 I 13 and (X‐PEA) 2 MA 3 Pb 4 I 13 (X = F, Cl, Br; n = 4), are illustrated in Figure S1, Supporting Information, along with the molecular structures of the spacer cations (PEA + , X‐PEA + ). [ 31 ] Figure a shows the molecular structures of PEA and X‐PEA cations, which contain a phenethylammonium or with halide atom substitution on the para‐ position on the conjugated phenyl ring. To explore the effect of the halogen substitution on the crystal structure of the Q‐2D RP perovskite, we first collected X‐ray diffraction (XRD) patterns of phase‐pure (PEA) 2 PbI 4 and (X‐PEA) 2 PbI 4 ( n = 1) films, as shown in Figure S2a, Supporting Information.…”

Centimeter‐Sized Single Crystal of Two‐Dimensional Halide Perovskites Incorporating Straight‐Chain Symmetric Diammonium Ion for X‐Ray Detection

“…[PbI 6 ] 4À and BDA 2+ are bound together by electrostatic interactions between the iodide anions and ammonium end group.Itistherefore expected to be difficult to exfoliate down to inorganic layer because of strong electrostatic interactions between inorganic layers,w hich is contrast to the (A) 2 A' nÀ1 M n Y 3n+1 type structure with monoammonium spacers where organic-inorganic layers are stacked through Va nd er Waals interaction between large organic spacers. [33] Meanwhile,t he [PbI 6 ] 4À layers slide in as taggered configuration because the BDA 2+ spacer is long enough to tilt. This structure is believed to belong to the Ruddlesden-Popper structure.…”

Centimeter‐Sized Single Crystal of Two‐Dimensional Halide Perovskites Incorporating Straight‐Chain Symmetric Diammonium Ion for X‐Ray Detection

“…[PbI 6 ] 4− and BDA 2+ are bound together by electrostatic interactions between the iodide anions and ammonium end group. It is therefore expected to be difficult to exfoliate down to inorganic layer because of strong electrostatic interactions between inorganic layers, which is contrast to the (A) 2 A′ n −1 M n Y 3 n +1 type structure with monoammonium spacers where organic‐inorganic layers are stacked through Van der Waals interaction between large organic spacers . Meanwhile, the [PbI 6 ] 4− layers slide in a staggered configuration because the BDA 2+ spacer is long enough to tilt.…”