Radiation‐Resilient Perovskite Solar Cells for Space Exploration: From Soft‐Lattice Dynamics to Stack‐Level Hardening

Perovskite solar cells (PSCs) have emerged as compelling candidates for next-generation space photovoltaics, offering high specific power, mechanical flexibility, and promising radiation tolerance. However, in orbit, these devices face a harsh radiation environment of energetic electrons, protons, gamma rays, ultraviolet (UV) photons, and other radiation sources such as neutrons and x-rays, together with vacuum, AM0 illumination, and temperature cycling. Here, we review radiation damage mechanisms and hardening strategies for PSCs under space-relevant conditions. We highlight that the soft ionic lattice and defect tolerance of halide perovskites enable dynamic self-healing capability, wherein non-ionizing energy loss (NIEL)-driven displacement damage competes with ionizing energy loss (IEL)-driven defect reorganization. Despite the perovskite absorber's exceptional radiation hardness, device-level failure is frequently dictated by the degradation of charge-transport layers, buried interfaces, metal contacts, substrates, and encapsulation layers. We then discuss hardening strategies, including compositional engineering, robust transport layers, interfacial passivation, and functional encapsulation. Finally, we outline key challenges limiting practical deployment, including the lack of standardized space-relevant testing protocols, insufficient understanding of multi-physics coupled space stressors, and the absence of predictive lifetime models. By bridging fundamental radiation physics with device engineering, this review provides a comprehensive roadmap for developing radiation-resilient perovskite photovoltaics for aerospace applications.