Hydration Intermediate Phase Regulated In‐Plane and Out‐Plane Epitaxy Growth of Oriented Nano‐Array Structures on Perovskite Single Crystals

Abstract

Fabrication of organic–metal‐halide perovskite micro‐nano array structures draws attention to the potential application in polarized light, high‐resolution X‑ray imaging, light‐emitting diodes, and lasers. However, it is still challenging to achieve the growth of controllable long‐range ordered nanostructure arrays by chemical solution‐based techniques. Herein, controllable epitaxial growth of long‐range ordered micro‐nano arrays on MAPbI3 single crystal (SC) surface is reported. A hydrated intermediate phase is found that can effectively regulate in‐plane and out‐plane orientated growth, respectively. This is attributed to the regulation of growth thermodynamics by hydration 0D perovskite intermediate phase enabling free recombination of PbI42– octahedral cages. Further, it is found that the degree of hydration is the key to the realization of in‐plane and out‐plane growth. Meanwhile, polarization emission and amplified spontaneous emission property are observed in highly oriented nanorod arrays with potential applications in anti‐counterfeiting polarized emission.

Micro/Nano Perovskite Materials for Advanced X-ray Detection and Imaging

“…In this intricate process, the key determinants for the perovskite’s final characteristics and performance include the carefully calibrated parameters of etching time, operating voltage, and current . Li et al made a significant breakthrough by developing a hydration intermediate phase regulated epitaxy growth technique, which enabled the fabrication of highly oriented nano arrays on bulk perovskite MAPbI 3 SCs (Figure a) . The arrays exhibited a preference for growth along the (110) crystal plane, showcasing great potential for anticounterfeiting applications.…”

Compositional gradient engineering and applications in halide perovskites

“…Owing to the same octahedral [PbBr 6 ] 4− sheets of (FAPEA 2 )PbBr 4 and FAPbBr 3 , the 2D layer is closely epitaxially grown on the surface of 3D SC, and the thickness of the 2D layer linearly increased from 6 to 13 to 19 μm as grown in the saturated solution for 3, 6, and 9 hours, respectively. Unlike the above epitaxial SCs layers, 2D HP layers can also be grown on the surface of SCs by simple liquid immersion 81 or spin-coating. 24…”

Intricate Reaction Pathways on CH3NH3PbI3 Photocatalysts in Aqueous Solution Unraveled by Single-Particle Spectroscopy

“…Notably, approximately half the bare MAPbI 3 nanoparticles in ambient air exhibited the same PL peak wavelengths as those (760 ± 5 nm) of OA-capped ones, while the others possess the peaks blue-shifted by approximately 10−20 nm (0.02−0.04 eV), possibly due to hydration (Figure S5). 32,33 After immersion in the solution, however, no such blue shift was observed. These results imply the dissolution and recrystallization of hydrated MAPbI 3 nanoparticles, leading to the formation of MAPbI 3 with a pristine crystal structure under dynamic equilibrium, in accordance with the XRD results (Figure 1d).…”