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

AbstractPolycrystalline 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 Gyair−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 Gyair−1 cm−2, accompanied by a notable increase in the minimum detection limit of 127.9 nGyair 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.