Additive Engineering for Ambient Blade-Coated CsPbBr3 Films Enabling High-Performance Self-Powered X-Ray Detection

Hybrid perovskite materials have recently emerged as a promising candidate in radiation detection research due to their superior charge carrier mobility and lower trap-state density. While most perovskite X-ray detectors typically rely on external bias for charge collection, the growing demand for efficient and energy-saving perovskite X-ray detectors has spurred extensive interest in self-powered devices, which offer high-performance, low power consumption, and enhanced portability. To date, most high-performance self-powered X-ray detectors rely on secondary crystal growth via post-deposition immersion in saturated solutions. Herein, we report a facile additive engineering strategy employing 4-trifluoromethyphenylammonium iodide (CF 3 PhAI) to modulate perovskite crystallization, enabling single-step fabrication of microcrystalline CsPbBr 3 films with grain sizes up to 38.6 µm. This approach effectively passivates defects and suppresses ion migration in CsPbBr 3 , reducing dark current drift by nearly two orders of magnitude from 4.135 × 10 −12 to 4.167 × 10 −14 A s −1 . Moreover, the incorporation of a low-work-function aluminum (Al) top electrode significantly enhances the built-in electric field, yielding a remarkable zero-bias sensitivity of 1.3 × 10 3 µC Gy air −1 cm −2 . This work accelerates the development of high-performance self-powered perovskite X-ray detectors toward practical applications.