Ionic transport characteristics of large-size CsPbBr3 single crystals

As a typical perovskite compound, cesium lead bromine (CsPbBr 3 ) has been widely studied because of its different kinds of optoelectronic applications. For high-energy ray detection, long-term stability of CsPbBr 3 single crystal detectors is affected by ionic transport when working under an applied bias. In this paper, the current-voltage hysteresis at different temperatures was investigated. The so-called temperature-dependent transient response measurements were used to study the ionic transport characteristics of CsPbBr 3 single crystal. The ionic migration mechanism was analyzed by comparing experimentally extracted ionic migration activation energies with theoretical results. The experimentally determined migration activation energy of ions of our CsPbBr 3 single crystals was well in agreement with the theoretically calculated value of bromine vacancies ( ), indicating that dominates the ionic migration in CsPbBr 3 single crystals. The dielectric behavior was also explored and it was revealed that dielectric polarization in CsPbBr 3 single crystals mainly ascribed to the mobile bromine ions via vacancy-mediated mechanism. These findings give us meticulous insight on ionic transport dynamics of CsPbBr 3 single crystals, which is critical for optimizing the devices with improved stability and efficiency.