Progress in the growth and high-efficiency detectors of perovskite single crystals such as Dalian Institute of Chemical Technology

[ China Instrument Network Instrument Development ] Recently, Liu Shengzhong, a researcher of the thin-film silicon solar cell research group of the Solar Research Department of the Dalian Institute of Chemical Physics, Chinese Academy of Sciences, and Zhao Kui, a professor of Shaanxi Normal University, have grown high-quality perovskite single crystals at low temperature gradients. New progress has been made in the study of high-efficiency photodetectors. Related research results are published on Materials Today under the title of Low-temperature-gradient crystallization for multi-inch high-quality perovskite single crystals for record performance photodetectors.

Although the organic inorganic halide perovskite single crystal has excellent photoelectric properties, the practical application of the single crystal material is currently limited due to the lack of a large-sized perovskite single crystal growth method. In this work, the research team reported for the first time a low-temperature gradient crystal growth method, successfully growing a high-quality CH3NH3PbBr3 perovskite single crystal larger than two inches. Theoretical analysis found that a small temperature gradient can effectively control the growth environment of the single crystal, especially to control the concentration of the solution in the optimal single crystal growth region.

Studies have shown that at temperatures below 60 degrees, as the temperature increases from room temperature to 60 degrees, the solubility changes very significantly with temperature; and above 60 degrees, the solubility changes with temperature very little even at elevated temperatures. This means that at lower temperatures (<60 degrees), it is ensured that a slower single crystal growth rate can be controlled while achieving higher yields to achieve controlled growth of high quality single crystals.

Based on the above findings, the researchers successfully designed a low-temperature gradient crystal growth method to obtain a high-quality CH3NH3PbBr3 perovskite single crystal with a size of 47×41×14 mm. Single crystals grown at low temperatures have lower defect density, higher mobility, and longer carrier diffusion length than single crystals grown at high temperatures. The quantum detector based on the high-quality single crystal has a quantum efficiency of up to 13453%, a detection rate of up to 8×10 13 jones, and a response speed of up to 15.8 μs, which are superior to the best performance of the material.

The above research work was supported by the National Key R&D Program, the Central University Basic Research Fund, the National Natural Science Foundation Project, the 111 Project, the Changjiang Scholar Innovation Team, and the China National Thousand Talents Program.

(Original title: Dalian Institute of Chemicals, etc. progress in the growth of perovskite single crystals and efficient detectors)