Short-pulsed proton irradiation stability in slot-die-coated bifacial perovskite photodetectors

Flexible perovskite-based photodetectors are emerging as promising candidates for next-generation optoelectronics, particularly in aerospace and radiation-intense environments. However, their stability under high-energy particle exposure remains insufficiently understood, especially for devices fabricated using scalable deposition methods. In this work, we investigate bifacial flexible perovskite photodetectors fabricated via slot-die-coating and subjected to short-pulsed (150 ns) 170 keV proton irradiation at fluences of 1012 and 5·1012 protons/cm2. The external quantum efficiency (EQE) decreased by ~ 30–40% after low-dose irradiation and by ~ 50% at higher fluence, with stronger losses observed for illumination through the MoO3/Au/MoO3 (dielectric-metal-dielectric, DMD) side. Spectral responsivity declined from 0.39 A/W (PET-side) and 0.30 A/W (DMD-side) in reference devices to 0.20 A/W and 0.16 A/W, respectively, after high-dose exposure. Similarly, peak detectivity dropped from 5.9·1011 Jones to ~ 3·1011 Jones, reflecting the combined effects of reduced charge collection and increased noise. These results demonstrate that flexible slot-die-coated bifacial perovskite photodetectors possess high radiation tolerance, highlighting the robustness of scalable device architectures for use in space, aerospace, and high-energy physics applications.