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

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 cm 3 ‐volume all‐inorganic perovskite CsPbBr 3 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 cm 3 ‐volume CsPbBr 3 SC ingots with trapping state density as low as of 1 × 10 9 cm −3 have been achieved by a modified Bridgman growth method. The volume reported here is the largest CsPbX 3 (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 CsPbBr 3 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 10 5 cm −1 , 3.7 cm per Goeppert‐Mayer (GM), 10 µm and 2000 cm 2 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 CsPbBr 3 SC photodetectors operated under the irradiation of both visible and IR light sources with light on/off ratio higher than 10 3 . These results demonstrate the CsPbBr 3 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.