Dual Defect Passivation Engineering of Perovskite Photodetectors toward Infrared Filter‐Free Full‐Color Imaging

Mainstream broadband photodetector‐based full‐color imaging systems rely on Bayer filters for spectral discrimination, which necessitates infrared cut filters to block near‐infrared light—a process that inevitably reduces optical transmittance and increases system weight. Perovskite photodetectors offer a promising infrared‐filter‐free alternative due to their spectrally tunable characteristics, with blade‐coating fabrication enabling large‐area scalable production. However, intrinsic defects and environmental instability severely limit their practical implementation. To address these challenges, a synergistic strategy is proposed that effectively suppresses iodide oxidation through guanidinium ion doping and concurrently employs in situ passivation using pre‐synthesized quasi‐2D perovskites, collectively reducing defect‐state density. The fabricated detector demonstrates key metrics toward full‐frame perovskite photodetectors, achieving defect density at 1.66 × 10 15 cm −3 , specific detectivity at 1.42 × 10 12 Jones, and photoresponse nonuniformity of 1.21% across the active area. Systematic stability assessments further confirm outstanding environmental robustness; the ultimately fabricated large‐area devices showed negligible change in switching characteristics after continuous operation for over 17 h and retained 90% of their initial EQE after 40 h under harsh conditions of 335.15 K and 80% relative humidity. Infrared‐filter‐free color imaging is demonstrated using a high‐performance photodetector, validating its tremendous potential for full‐color imaging applications.