Surface Effect on 2D Hybrid Perovskite Crystals: Perovskites Using an Ethanolamine Organic Layer as an Example

Abstract

Despite the remarkable progress of optoelectronic devices based on hybrid perovskites, there are significant drawbacks, which have largely hindered their development as an alternative of silicon. For instance, hybrid perovskites are well‐known to suffer from moisture instability which leads to surface degradation. Nonetheless, the dependence of the surface effect on the moisture stability and optoelectronic properties of hybrid perovskites has not been fully investigated. In this work, the influence of the surface effect of 2D layered perovskites before and after mechanical exfoliation, representing rough and smooth surfaces of perovskite crystals, are studied. It is found that the smooth 2D perovskite is less sensitive to ambient moisture and exhibits a considerably low dark current, which outperforms the rough perovskites by 23.6 times in terms of photodetectivity. The superior moisture stability of the smooth perovskites over the rough perovskites is demonstrated. Additionally, ethanolamine is employed as an organic linker of the 2D layered perovskite, which further improves the moisture stability. This work reveals the strong dependence of the surface conditions of 2D hybrid perovskite crystals on their moisture stability and optoelectronic properties, which are of utmost importance to the design of practical optoelectronic devices based on hybrid perovskite crystals.

Organic‐Inorganic Hybrid Perovskite Single Crystals: Crystallization, Molecular Structures, and Bandgap Engineering

“…Furthermore, the bulk inorganic hybrid perovskite single crystals can be exfoliated into few layers. [70][71][72][73][74][75] Therefore, the thickness of organicinorganic hybrid perovskite can be as thin as 2 nm after exfoliation. Besides the methods mentioned above, melt crystallization techniques such as Czochralski method, Bridgman method and zone-melting method can be also employed to grow large-size industrially important functional crystals.…”

Low‐Dimensional Perovskites with Diammonium and Monoammonium Alternant Cations for High‐Performance Photovoltaics

“…Low‐dimensional Ruddlesden–Popper (LDRP) perovskites have recently emerged as the viable photovoltaic materials due to their large formation energy, superior photothermal stability, insensitivity to moisture and ultralow self‐doping effect . Unlike the more roundly expanded 3D perovskites, LDRP perovskites with chemical formula of (A) 2 MA n −1 Pb n I 3 n +1 (where A is alkylammonium cation and n is the number of inorganic slabs) are considered as infinite nanoplatelets with atomic or molecular size obtained by quantizing the number of [PbI 6 ] 4− octahedra layers between organic ligands which causes quantum and dielectric confinement along one axis . These ultrathin perovskite nanoplatelets are assembled together by intercalating organic cations (Van der Waals force), which protects the degradation of lattice by water and oxygen, resists ion migration and maintains the structural integrity of the 2D and quasi‐2D (q‐2D) perovskites .…”

Induced dielectric behavior in high dense AlxLa1-xTiO3 (x = 0.2–0.8) nanospheres

“…That is, in few cases, the A-site cation may be divalent or trivalent while the B-site cation may be tetravalent. However, these perovskite materials acquired much significance for the past decades due to their versatile structural, optical, morphological, electrical, ferroelectric, piezoelectric, physical, and chemical properties [2][3][4][5][6][7][8]. In view of this, LaTiO 3 (LT) is considered as a good candidate material in performing few of the above mentioned properties.…”