Enhanced Performance of Perovskite Single-Crystal Photodiodes by Epitaxial Hole Blocking Layer

MAPbX3 Perovskite Single Crystals for Advanced Optoelectronic Applications: Progress, Challenges, and Perspective

Perovskite single crystals have garnered significant attention due to their impressive properties in optoelectronic applications, including long carrier diffusion lengths, low trap-state densities, and enhanced stability. Methylamino lead halide perovskite (MAPbX3, where X is a halogen such as Cl, Br, or I) is a notable example of a metal halide perovskite with desirable properties and ideal cubic perovskites with a tolerance factor between 0.9 and 1.0. MAPbX3 has adjustable bandgap, high thermal and chemical stability, and excellent light absorption capacity. Here the unique characteristics of MAPbX3, including molecular structure, optical absorption properties, and carrier transport of MAPbX3 single crystals are summarized. Universal growth technologies for MAPbX3 single crystals, including inverse temperature crystallization, anti-solvent evaporation crystallization, solvent evaporation method, and single-crystalline thin film, including epitaxial method and space limiting method, are briefly introduced. Additionally, a comprehensive review of MAPbX3 single crystals in various optoelectronic device applications, including photodetectors, X-ray detectors, light-emitting diodes, lasers, and solar cells is mainly discussed. Finally, the current challenges and future prospects of the large-scale preparation and growth of MAPbX3 single crystals are put forward. With the continuous progress of photoelectric technology, more innovative photoelectric applications in the future are expected to bring more convenience and progress.

Halide perovskite single crystals: growth, characterization, and stability for optoelectronic applications

Recently, metal halide perovskite materials have received significant attention as promising candidates for optoelectronic applications with tremendous achievements, owing to their outstanding optoelectronic properties and facile solution-processed fabrication. However, the existence of a large number of grain boundaries in perovskite polycrystalline thin films causes ion migration, surface defects, and instability, which are detrimental to device applications. Compared with their polycrystalline counterparts, perovskite single crystals have been explored to realize stable and excellent properties such as a long diffusion length and low trap density. The development of growth techniques and physicochemical characterizations led to the widespread implementation of perovskite single-crystal structures in optoelectronic applications. In this review, recent progress in the growth techniques of perovskite single crystals, including advanced crystallization methods, is summarized. Additionally, their optoelectronic characterizations are elucidated along with a detailed analysis of their optical properties, carrier transport mechanisms, defect densities, surface morphologies, and stability issues. Furthermore, the promising applications of perovskite single crystals in solar cells, photodetectors, light-emitting diodes, lasers, and flexible devices are discussed. The development of suitable growth and characterization techniques contributes to the fundamental investigation of these materials and aids in the construction of highly efficient optoelectronic devices based on halide perovskite single crystals.

Biphasic Liquid-Liquid Interface Limit Architecture of High-Quality Perovskite Single-Crystal Sheets for UV Photodetection

Thin organic-inorganic MAPbX₃ perovskite single-crystal sheets have become the hotspot of smart photodetectors because of their low number of trap states, high carrier mobility, long diffusion length, and effective light-receiving area. However, MAPbX₃ single crystals are so fragile that single-crystal perovskite sheets with a thickness of ≤100 μm are hard to obtain by cutting. Thin single-crystal MAPbX₃ sheets were synthesized by the biphasic liquid-liquid interface limit method with dimethicone/DMSO biphasic films and could be obtained with an adjustable thickness of 1-50 μm and improved crystal quality of the perovskite sheets. The thin MAPbX₃ single-crystal sheet-based photodetector exhibits a superior responsivity of 0.88 A W^-1, an external quantum efficiency of 276.8%, and an ultrahigh detectivity of 2.26 × 10¹¹ Jones under 395 nm irradiation at 3 V. These values are more than 500% as high as those of the bulk-crystal-based photodetector. In particular, the sheet-based photodetector could retain long-time stability after 4200 on-off cycles.

Photodiodes based on a MAPbBr3/Bi3+-doped MAPbCl3 single crystals heterojunction for the X-ray detection

The epitaxially fabricated MAPbBr₃/Bi³⁺-doped MAPbCl₃ PSCs pN heterojunction shows advanced X-ray detection performance with decreased dark current density and faster response time under relatively high external reverse voltage.