Record stability for perovskite-based X-ray detectors through the use of polymeric template.

Lead-halide hybrid perovskites are recently emerging as promising materials for high energy radiation detection thanks to the combination of high absorption coefficient, excellent transport properties, even in polycrystalline films, and their solution processability. Here we present perovskite based X-ray detectors employing a perovskite-polymer (starch) composite thin film as active layer. The use of starch as template for the perovskite growth allows a precise control of the active layer thickness and compactness, and confers to the device exceptional stability and performances. The performances of the active perovskite layer, inserted in a photodiode architecture, were studied under $40 {kV}$ X-ray radiation. Different thicknesses were used and the top sensitivity of $5.5\pm$ 0.2 $\mu$ C\, Gy^$-1$\, $cm^{-2}$ was measured for $1050 {nm}$ perovskite thickness operating in passive mode ({0 ${V}$). Here we report the longest aging test on perovskite X-ray detectors up to date. We stored the samples in air for 629 days tracking the performance degradation. At the end of the experiment, the detector with $20%$wt of starch retained $97%$ of the initial sensitivity.