Visual directional growth device and growth method for large-size bromine-lead-cesium single crystal

Abstract

The invention relates to a visual directional growth device and a growth method for a large-size bromine-lead-cesium single crystal. The device comprises a furnace body and a rotary descending system,wherein the furnace body comprises a quartz furnace tube and a heating device, a cavity in the quartz furnace tube is a crystal growth cavity, the heating device is arranged outside the quartz furnace tube, a heat insulation sleeve is sleeved outside the heating device of the quartz furnace tube, a crystal growth crucible is arranged in the crystal growth cavity, the bottom of the crystal growthcrucible is a seed crystal bag, and CsPbBr3 seed crystals are arranged in the seed crystal bag; and the rotary descending system comprises a long crystal rod and a driving device for driving the longcrystal rod to rotate and descend, and the seed crystal bag is fixed on the long crystal rod. The CsPbBr3 single crystal obtained by the visual directional growth device is large in size and good in crystal transparency, and the device is beneficial to discharging of impurities in the crystal growth process, and adopts a slow cooling rate to prevent the crystal from cracking.

Description

technical field [0001] The invention relates to a visual directional growth device and a growth method for large-size bromine-lead-cesium single crystals, belonging to the technical field of crystal growth. Background technique [0002] In recent years, halogen perovskite materials have shown broad application prospects in the fields of solar cells, light-emitting diodes, photoelectric detection, and nuclear radiation detection. Compared with organic-inorganic composite halogen perovskite materials, the all-inorganic halide perovskite crystal bromide lead cesium (molecular formula: CsPbBr 3 ) has excellent characteristics of insensitivity to temperature, light and moisture in the air, and the stability of materials and devices is better. [0003] Cesium lead bromide (CsPbBr 3 ) single crystal has the following advantages as a room temperature nuclear radiation detector material: CsPbBr 3 The crystal has a large atomic number (Pb: 82, Cs: 55, Br: 35), and a moderate band g...

AI Technical Summary

Problems solved by technology

However, the melt-grown CsPbBr 3 There are still some problems that cannot be ignored in single crystal: (1) CsPbBr 3 Single crystal growth cannot be observed in real time, and parameter adjustments cannot be made according to the real-time growth status. Only after the crystal growth is completed and the temperature is lowered to take out the crystal can it be known whether it has grown into a single crystal; (2) The current melt method grows CsPbBr 3 For spontaneous nucleation, it is easy to generate polycrystalline, which affects the quality of single crystal growth; (3) CsPbBr 3 The crystal has two phase transition points at 89°C and 130°C, and the crystal grown by the melt method will undergo a phase transition during the cooling process, which will easily lead to cracks in the crystal, and the transparency of the grown crystal is poor

Therefore, CsPbBr 3 Single crystal growth still faces many difficulties and challenges, such as the growth process cannot be observed, the crystal size is small, the crystal is easy to crack, the crystal transparency is poor, and the crystal is difficult to grow directional.

[0006] In addition, there is currently no dedicated large-scale CsPbBr 3 Report on Visual Growth Device of Single Crystal

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