关键词: 钙钛矿单晶, CsPbCl₃晶体, 坩埚下降法, 光学带隙, 低温荧光光谱, 激子结合能

Abstract: CsPbX₃(X=Cl^-, Br^-, I^-) pervoskite single crystals have excellent photoelectric properties, and are promising to become the next generation of photoelectric detection materials. It is difficult to grow CsPbCl₃ crystals by low-temperature solution method due to the solubility of CsCl in the precursor is too small. Here, 1 inch complete CsPbCl₃ crystals were grown by Bridgman method, a series of processing was performed on the crystals to obtain single crystal sheets of ø10 mm×10 mm and 2 mm thickness. X-ray powder diffraction patterns, TG/DTA curves, X-ray excitation emission spectra, transmission spectra and low temperature fluorescence spectra of the crystals were measured. Under X-ray excitation, two X-ray excitation peaks are observed at 430 and 575 nm, and the transmittance of the crystal reaches 75%; thermal quenching could be observed by the photoluminescence (PL) intensity versus temperature dependence curve, and the exciton binding energies of the four peaks of the crystal are calculated to be 12.59, 8.21, 12.41 and 21.59 meV, respectively.

Key words: perovskite single crystal, CsPbCl₃ crystal, Bridgman method, optical band gap, low temperature fluorescence spectroscopy, exciton binding energy