Out‐Of‐Phase Articulation Strategy of CsPbBr₃/CsPb₂Br₅ Perovskite for High Sensitivity X‐Ray Detection

Abstract Polycrystalline CsPbBr₃ perovskite materials exhibit exemplary stability, and desirable optoelectronic characteristics are promising for direct X‐ray detection. In this study, polycrystalline 2D phase of CsPb₂Br₅ hinged on CsPbBr₃ is investigated for X‐ray array detector. The incorporation of CsPb₂Br₅ will modify the carrier transport environment, acting as an amplification factor that significantly enhances carrier mobility and response sensitivity. Finally, the devices demonstrates excellent performance growth. Carrier mobility of CsPbBr₃ is improved by a significant 2 orders of magnitude, leading to the sensitivity increased from 2.64 × 10⁴ to 2.58 × 10⁵ µC Gy_air⁻¹ cm⁻² at a bias voltage of 25 V mm⁻¹. Even at a low bias voltage of 2 V mm⁻¹, still got the value of 3.075 × 10³ µC Gy_air⁻¹ cm⁻², accompanied by a notable increase in the minimum detection limit of 127.9 nGy_air s⁻¹ at 0.5 V. Furthermore, a high modulation transfer function (MTF) of 1.57 lp mm⁻¹ is obtained, and achieved a clear and high contrast X‐ray imaging with 64 × 64 TFT board. The perovskite exhibits outstanding light stability (RH ≈ 70 ± 5%) in the atmosphere following the introduction of 2D phase. This excellent carrier transport effect and good long‐term stability present significant commercial potential.