Exploring Anisotropy on Oriented Wafers of MAPbBr₃ Crystals Grown by Controlled Antisolvent Diffusion

Abstract

The emergence of organic–inorganic halide perovskites has reformed the research status of optoelectronics to a great extent. The bulk single crystals of halide perovskite, which in theory reflect the intrinsic physical properties of the material, are however hard to integrate into functional devices. Just as in the case that silicon wafers have revolutionized modern industries including electronics and solar cells, the availability of perovskite crystal wafers may pave the way to functional devices. Here we designed a new settled temperature and controlled antisolvent diffusion system to precisely control all key factors that affect the supersaturation metastable zone during the crystal growth process, to grow MAPbBr3 single crystals more than 50 mm in size. Second, we fabricated MAPbBr3 single crystal wafers with different orientations, specifically, the (100), (010), (001), (110), and (111) wafers, with high crystalline quality (half-peak width of rocking curve of 60–100 arc sec). Some key parameters were measured and compared on the wafers, where the results hint that anisotropy of carrier transport may exist for this pseudocubic structure. We hope the availability of oriented single-crystal wafers can provide more scientists the materials and devices to clarify the debatable physicochemical properties and to integrate the wafers as active layers or substrates in optoelectronic devices.

Managing grains and interfaces via ligand anchoring enables 22.3%-efficiency inverted perovskite solar cells

“…We acquired temperature-dependent capacitance versus frequency (C-f) plots to probe trap density and the energy depth of trap states (see supplementary materials). AALs have the potential to suppress trap density directly by filling in A-site vacancies and modifying grains and interfaces; additionally, they have the potential to provide a similar benefit by promoting the (100) orientation of grains in perovskite films 60 , which may have a different susceptibility to surface-defect formation than other random orientations in the pristine perovskite films 61,62 . To further investigate this possibility, we studied the dependence of trap density on the surface crystallographic facets using density functional theory (DFT) calculations based on a cubic FAPbI3 model 63,64 .…”

Halide Perovskite Single Crystals: Optoelectronic Applications and Strategical Approaches

“…The MAPbBr 3 and MAPbI 3 crystals shown in Figure 2b were obtained within one week of crystallisation. Figure 2c shows a modified AVC setup where a temperature controller and a flow controller are used to ensure a stable environment and continuous antisolvent diffusion for high-quality and large single crystals [67]. A large MAPbBr 3 single crystal over 50 mm in size was grown with this modified method ( Figure 2d) after over-15-day synthesis.…”

Charge Transport in Halide Perovskite Single Crystals: Experimental and Theoretical Perspectives

“…The schemes of various solution growth methods, including seeded solution growth, anti‐solvent diffusion crystallization,, and inverse temperature crystallization, and the resulting crystals are shown in Figure . Besides solution growth methods, vapor‐phase epitaxial growth has also been shown to produce single crystalline HaP thin films …”