High-Performance Electron Transport in CsPbBr3 Perovskite Crystals for Room-Temperature Radiation Detection

Abstract

All-inorganic CsPbBr₃ perovskite material has gained considerable attention in recent years for its unique properties, including exceptional room-temperature semiconductor behavior for hard radiation detection. This semiconductor has achieved record-breaking energy resolutions in room-temperature gamma-ray detection. Despite the high energy resolutions achieved, performance in CsPbBr₃ detectors has primarily relied on hole collection due to the lower likelihood of hole trapping in halide perovskites, leaving the potential of electron transport largely underexplored. In this study, we explore the electron transport properties of Bridgman-grown CsPbBr₃ crystals with thicknesses below 2 mm. Remarkably, we demonstrate high spectral performance using electron collection, achieving energy resolutions of 2.5% for ¹³⁷Cs (662 keV), 4.2% for ⁵⁷Co (122 keV), and 7.8% for ²⁴¹Am (59.5 keV). These results are comparable to those obtained via hole collection. The mobility–lifetime (μ·τ) product value for electrons reached ∼1.03 × 10^–3 cm²/V. Furthermore, mobilities estimated through pulse rise time analysis yielded similar values of ∼27 cm²/(V s) for both electrons and holes. This work provides the first systematic evidence that electron collection is viable in thin CsPbBr₃ detectors, highlighting their potential for use in high-performance radiation detection by electron collection.