Capillary Force-Assisted\nCsPbBr<sub>3–<i>x</i></sub>I<sub><i>x</i></sub> (<i>x</i> = 0, 1) Columnar Crystal Film for X‑ray\nDetectors with Ultrahigh\nElectric Field and Sensitivity

Inorganic halide perovskite thin-film X-ray detectors\nhave attracted\ngreat research interest in recent years due to their high sensitivity,\nlow detection limit, and facile fabrication process. The poor crystal\nquality of the thin film with uncontrollable thickness and low background\nvoltage during detection limits its practical application. Here, a\nhigh-quality CsPbBr<sub>3–<i>x</i></sub>I<sub><i>x</i></sub> (<i>x</i> = 0, 1) columnar crystal film\nis prepared by an improved melt-confined method with a porous anodic\naluminum oxide (AAO) template, which stabilizes the disorder perovskite\nsystems of CsPbBr<sub>2</sub>I by stress. The AAO-CsPbBr<sub>3–<i>x</i></sub>I<sub><i>x</i></sub> (<i>x</i> = 0) detectors exhibit high detection accuracy and photoelectric\nconversion capability with an ultrahigh sensitivity of 32,399.5 μC·Gy<sub>air</sub><sup>–1</sup>·cm<sup>–2</sup> at 2142.9\nV mm<sup>–1</sup> under 20 kV<sub>p</sub> X-rays and 19,217.4\nμC·Gy<sub>air</sub><sup>–1</sup>·cm<sup>–2</sup> with a higher background electric field of 6666.7 V mm<sup>–1</sup> for AAO-CsPbBr<sub>3–<i>x</i></sub>I<sub><i>x</i></sub> (<i>x</i> = 1). Moreover, the AAO-CsPbBr<sub>3–<i>x</i></sub>I<sub><i>x</i></sub> (<i>x</i> = 1) film detector acquires a lower detection limit of\n7.65 nGy·s<sup>–1</sup> and a higher X-ray imaging spatial\nresolution of 1.6 LP/mm and 8.6 nGy·s<sup>–1</sup> and\n1.4 LP/mm for AAO-CsPbBr<sub>3–<i>x</i></sub>I<sub>x</sub> (<i>x</i> = 0). The facile, high-quality columnar\ncrystal film devices display great potential for low-energy and low-dose\nX-ray imaging in flat panel detection applications.