Facilitating All‐Inorganic Halide Perovskites Fabrication in Confined‐Space Deposition

Abstract

Abstract2D all‐inorganic halide perovskites (2D AIHP) have attracted huge attention for their excellent optoelectronic properties and superior atmospheric stability for organic–inorganic halide perovskites. 2D AIHP has been fabricated by varied strategies, whereas a satisfied way to simultaneously reach good quality, dimensions, and uniformity is still far from achieved yet. Here, a direct thermal deposition method to synthesize 2D AIHP of lateral length up to ≈30 µm and uniform thickness down to ≈10 nm, which shows excellent optoelectronic performance comparable to the reported top‐level 2D AIHP, is proposed. A vertical mass transport instead of conventional horizontal mode is adopted, significantly enhancing the deposition stability. Furthermore, the morphologies of AIHP are switchable between nanowires and nanoflakes under the control of deposition temperature. This method may pave the way for uniform fabrication of 2D AIHP or AIHP‐based 2D heterostructures for various applications.

Recent Progress on Two-Dimensional Materials

“…3c). For other 2D materials, Wang et al achieved the preparation of 2D all-inorganic halide perovskites (2D AIHP) with adjustable morphologies via a vertical mass transport with the space-confined channel 207 . Confined spaces can improve the vapor pressure of sulfur, so that PtS2 thin films can be readily achieved in a scalable and controlled manner in a modified quartz tube 208 .…”

2D Cs2AgBiBr6 with Boosted Light–Matter Interaction for High‐Performance Photodetectors

“…In general, the preparation method for 2D inorganic perovskites can be classified into liquid phase synthesis and vapor phase deposition. [14,[23][24][25][26] The liquid synthesis approach typically replies on the crystallization strategies from solvent. [27] For example, 2D CsPbX 3 (X = Cl, Br, I) nanoplatelets with edge length of ≈100 nm have been successfully synthesized by a simple ligand-mediated reprecipitation strategy.…”

“…[36] The precursor concentration and the spacing between the restricted gap were found to be the key factors affecting the thickness and size of Cs 2 AgBiBr 6 nanoflakes. [24,37] Certain external force was applied on the backside of sapphire and SiO 2 substrates to tune the gap spacing for the synthesis of Cs 2 Ag-BiBr 6 nanoflakes. Figure S3a in the Supporting Information shows the Cs 2 AgBiBr 6 flakes obtained under various pressures (0-50 kPa) and precursor concentrations (0.01-0.04 mol L −1 ) at the same heating temperature.…”

2D Perovskite Single Crystals for Photodetectors: From Macro‐ to Microscale

“…[85] Furthermore, the all-inorganic 2D CsPbBr 3 crystal was obtained with a more uniform thickness and morphology by an improved CVD method (Figure 9e). [86] CsPbX 3 nanosheets were synthesized by controlling the temperature of evaporation. The results show that the CsPbBr 3 nanosheet has a thickness of %7 nm and a length of 10-30 μm (Figure 9f ).…”