Ultralarge All‐Inorganic Perovskite Bulk Single Crystal for High‐Performance Visible–Infrared Dual‐Modal Photodetectors

Abstract

Visible‐infrared dual‐modal light harvesting is crucial for various optoelectronic devices, particularly for solar cells and photodetectors. For the first time, this study reports on large 25 cm3‐volume all‐inorganic perovskite CsPbBr3 single crystal (SC) with an emphasis on the observed visible‐infrared dual‐modal light harvesting and sensing as demonstrated by the high‐performance visible‐infrared dual‐modal photodetectors. First, ultralarge 25 cm3‐volume CsPbBr3 SC ingots with trapping state density as low as of 1 × 109 cm−3 have been achieved by a modified Bridgman growth method. The volume reported here is the largest CsPbX3 (X = Cl, Br, I) all‐inorganic perovskite system up to now, and the SC can be facilely cut into SC wafers with a diameter of 25 mm for various optoelectronic devices. Furthermore, these CsPbBr3 SCs exhibit a visible absorbance coefficient, a near‐infrared (IR) two‐phonon absorption coefficient, a carrier diffusion length, and a mobility as high as of 105 cm−1, 3.7 cm per Goeppert‐Mayer (GM), 10 µm and 2000 cm2 V−1 s−1, respectively. These merits match well to the requirements of high‐performance Vis‐IR dual‐modal light harvesting optoelectronic devices, which has been demonstrated by the CsPbBr3 SC photodetectors operated under the irradiation of both visible and IR light sources with light on/off ratio higher than 103. These results demonstrate the CsPbBr3 SCs with high visible‐infrared dual‐modal light harvesting capability and excellent electrical transporting properties have a huge potential in various optoelectronic devices, such as solar cells, photodetectors, and lasers.

Recent Progress on Photomultiplication Type Organic Photodetectors

“…Although both the broadband and narrowband photodetectors have already achieved high performance, these photodetectors can exclusively operate under single spectral response model and consequently exhibit single response spectrum, limiting their broader applications. Realizing highly sensitive multifunctional photodetectors with tunable spectral response ability would meet the need of versatility in practical application …”

Metal halide perovskite nanocrystals and their applications in optoelectronic devices

“…Compared with polycrystalline films, single crystal perovskites can reduce the intragrain and intergrain defects that affect device performance and generally have good thermal stability and humidity stability compared with NCs. Therefore, single crystal perovskites are competitive with perovskite NCs . Despite this, perovskite NCs lead the development of this field with their outstanding characteristics, and researchers are actively working to solve those shortcomings and to make them efficient and stable for the next generation of optoelectronics.…”

Metal Halide Perovskites: Synthesis, Ion Migration, and Application in Field‐Effect Transistors

“…At the aspect of all‐inorganic perovskite single crystals, our group recently reported an ultralarge 25 cm 3 volume CsPbBr 3 single crystal ingot with a low trapping state density of 1.2 × 10 9 cm −3 . The CsPbBr 3 single crystal ingot was synthesized by a modified vertical Bridgman technique, in which equimolar amounts of CsBr and PbBr 2 were reacted in a fused silica ampoule . Figure f demonstrates the CsPbBr 3 single crystal ingot with a length of 7 cm.…”

“…Moreover, the PL process of the CsPbBr 3 single crystal can be realized not only by one‐photon, but also by two‐photon (energy smaller than the bandgap accompanied a virtual state) light excitation, as demonstrated in Figure h. This visible and infrared dual‐modal photosensitivity of the CsPbBr 3 single crystal renders it as a good candidate for new advanced optoelectronics …”