Defective states in micro-crystalline CsPbBr 3 and their role on photoconductivity

Intrinsic defects in CsPbBr3 microcrystalline films have been studied using thermally stimulated current (TSC) technique in a wide temperature range (100–400 K). Below room temperature, TSC emission is composed by a set of several energy levels, in the range 0.11–0.27 eV, suggesting a quasi-continuum distribution of states with almost constant density. Above room temperature, up to 400 K, the temperature range of interest for solar cells, both dark current and photocurrent, are mainly dominated by energy levels in the range 0.40–0.45 eV. Even if measured trap densities are high, in the range 1013–1016 cm3, the very small capture cross-sections, about 1026 m2, agree with the high defect tolerance characterizing this material.