Metal halide perovskites (MHPs) are emerging as promising materials for next-generation radiation detectors due to their high atomic number, efficient X-ray absorption, low exciton binding energy, and unique electronic structure, which enhances charge carrier mobility and collection efficiency [1-3]. Furthermore, their solution processability and mechanical flexibility make them ideal for integration into lightweight, flexible X-ray detector designs. In this work, we report the fabrication and characterization of lightweight perovskite-embedded membranes (PEMs) by spin-coating triple-cation perovskite onto hydrophilic membranes. The detectors were tested under continuous X-ray irradiation using a laboratory X-ray source and pulsed X-ray conditions at the KMC-3 XPP beamline of BESSY II, enabling comprehensive performance evaluation in diverse radiation environments. Pulsed X-ray testing was conducted with energies ranging from 7 keV to 16 keV and at different voltages.

With this approach, a sensitivity of 0.97 × 10⁵ μC/Gy_air.cm² under continuous 8 keV irradiation at a dose rate of 0.094 µGy_air/s at 100 V was achieved. Additionally, we investigated the impact of polymer treatment on the X-ray detection performance. By adding polymers, we further increased the sensitivity to 2.38 × 10⁵ μC/Gy_air.cm² for the polymer-treated devices under the same conditions.

Our results show that polymer treatment improves the photoluminescence quantum yield (PLQY) and increases the crystallinity of the perovskite at the 100 planes, indicating enhanced material quality. These improvements correlate with a notable increase in X-ray sensitivity in the polymer-treated devices.

Notably, the detectors demonstrated X-ray response even at 0 V, with polymer-treated device showing a sensitivity of 0.93 × 10² μC/Gy_air.cm², while the control devices showed a sensitivity of 0.42 × 10² μC/Gy_air.cm² under continuous 8 keV irradiation at a dose rate of 184.7 µGy_air/s. Under both continuous and pulsed X-ray conditions, polymer-treated devices consistently outperformed untreated controls, underscoring their superior performance and robustness.

The polymer additives act as passivation agents, reducing defect states and improving charge transport properties, which contribute to the enhanced X-ray detection performance. These findings position polymer treatment as a key strategy for optimizing the performance of flexible perovskite X-ray detectors.

In conclusion, this study demonstrates the feasibility of developing high-performance, flexible perovskite X-ray detectors with enhanced sensitivity. These advancements open the path towards lightweight, portable, and wearable radiation monitoring systems, creating new opportunities for advanced radiation detection.