Electronic‐Grade High‐Quality Perovskite Single Crystals by a Steady Self‐Supply Solution Growth for High‐Performance X‐ray Detectors

Abstract

High‐quality perovskite single crystals with large size are highly desirable for the fundamental research and high energy detection application. Here, a simple and convenient solution method, featuring continuous‐mass transport process (CMTP) by a steady self‐supply way, is shown to keep the growth of semiconductor single crystals continuously stable at a constant growth rate until an expected crystal size is achieved. A significantly reduced full width at half‐maximum (36 arcsec) of the (400) plane from the X‐ray rocking curve indicates a low angular dislocation of 6.8 × 106 cm−2 and hence a higher crystalline quality for the CH3NH3PbI3(MAPbI3) single crystals grown by CMTP as compared to the conventional inverse temperature crystallization (ITC) method. Furthermore, the CMTP‐based single crystals have lower trap density, reduced by nearly 200% to 4.5 × 109 cm−3, higher mobility increased by 187% to 150.2 cm2 V−1 s−1, and higher mobility–lifetime product increased by around 450% to 1.6 × 10−3 cm2 V−1, as compared with the ITC‐grown reference sample. The high performance of the CMTP‐based MAPbI3 X‐ray detector is comparable to that of a traditional high‐quality CdZnTe device, indicating the CMTP method as being a cost‐efficient strategy for high‐quality electronic‐grade semiconductor single crystals.

Triple‐Cation and Mixed‐Halide Perovskite Single Crystal for High‐Performance X‐ray Imaging

“…They are advantageous in strong X‐ray absorption, processable at low temperature, low‐cost fabrication, and superior semiconducting properties like low defect density, large mobility–lifetime product ( μτ ), long carrier diffusion length, etc. Noticeably, the recently reported X‐ray detectors based on 3D perovskites including MAPbI 3 [ 4,10–12 ] and CsFAMA [ 13 ] microcrystalline thin films or MAPbX 3 (X = Cl, Br, I and their mixture), [ 14–24 ] Cs x FA 1− x PbI 3 , [ 25 ] CsPbBr 3 , [ 26–29 ] and Cs 2 AgBiBr 6 [ 30–32 ] single crystals have realized high sensitivity with the highest up to 2.1 × 10 4 µC Gy air –1 cm –2 , significantly larger than the state‐of‐the‐art α‐Se X‐ray detectors. [ 33 ]…”

Ligand assisted growth of perovskite single crystals with low defect density

“…All solution-based single crystal growth methods create supersaturated solution so that solute can precipitate out. Among them, crystal growth through inverse temperature crystallization (ITC) method is particularly attractive, which utilizes the reduced solubility of perovskites in different solutions at a range of higher temperature [23][24][25] . To obtain large-sized bulk single crystals, the single crystal was carefully transferred as seed to another fresh precursor for multiple cycles 26 or using oil to continuously extract solvents 27 .…”

Great Amplification of Circular Polarization Sensitivity via Heterostructure Engineering of a Chiral Two-Dimensional Hybrid Perovskite Crystal with a Three-Dimensional MAPbI3 Crystal

“…Generally, for a solution with a concentration above the solubility curve (i.e., supersaturated), spontaneous nucleation will occur and corresponding growth rate is high. 47 Therefore, in experimental step 1 mentioned above, a stable unsaturated region was chosen to grow large 2D perovskite crystals, as denoted by the green dot and characterized by the presence of sizable crystals in a slow temperature-cooling procedure. For step 2, we note that only supersaturated MAPbI 3 solution gives the quick epitaxial growth of the surface layer.…”