Assessment of carrier transport properties of perovskite CsPbCl3 single crystal with time-of-flight alpha-particle response

摘要: All-inorganic CsPbCl₃ perovskite is a promising material for high-performance radiation detection owing to its extraordinary photoelectric properties and chemical stability. The critical challenge in developing widebandgap CsPbCl₃ perovskite lies in the quantitative assessment of its charge transport properties, which regulate its performance optimization. Herein, we report the first spectroscopic α particles using CsPbCl₃ detectors with asymmetric contact. CsPbCl₃ single crystals (ϕ 15 × 50 mm³) were successfully grown using the Bridgman melt method and subsequently fabricated into Schottky-type Bi/CsPbCl₃/Au detectors. Owing to its high electrical resistivity of 1.25 × 10⁹ Ω· cm, the CsPbCl3 detector demonstrated a low dark current density (∼870 nA/cm²) and stable performance. The CsPbCl₃ detector was also capable of resolving both the α particle (5.5 MeV) and γ-ray (59.5 keV) peaks from the ²⁴¹Am radioactive isotope. Furthermore, the carrier transport properties of CsPbCl₃ were evaluated quantitatively by the time-of-flight technology using ²⁴¹Am α particle response, revealing the hole and electron mobilities as ∼11.12 and ∼12.92 cm²·V⁻¹·s⁻², respectively. Meanwhile, the hole and electron mobility–lifetime products were obtained as ∼1.72 × 10⁻⁴ and ∼1.04 × 10⁻⁴ cm²·V⁻¹, respectively. The planar CsPbCl₃ detector achieved an excellent energy resolution of ∼14.9% at 122 keV under γ-ray exposure, which is the highest energy resolution reported to date for CsPbCl₃ detectors. This study highlights the considerable potential of inorganic perovskite detectors for radiation detection and provides a practical approach for the future development of perovskite materials.