Supramolecular Self‐Assembly of Organic Cu(I) Iodides as Green and Recyclable Paper‐Based Customizable Large‐Area Flexible Film for Plant Grow Lighting and Plant Root X‐Ray Imaging

Abstract Regarding global energy scarcity issues, it is imperative to establish sustainable plant production systems to promote smart agriculture. Addressing the critical demands of plant lighting and X‐ray imaging in smart agriculture, a recyclable luminescent flexible film is developed on a filter paper and organic Cu(I) metal iodide, and establishes a bifunctional platform integrating plant growth lighting and plant root X‐ray imaging. Specifically, [Ca(15‐crown‐5) ₂ ]Cu ₄ I ₆ ·2C ₃ H ₇ NO·H ₂ O and [Ca ₂ (18‐crown‐6) ₄ ]Cu ₄ I ₈ ·6H ₂ O are synthesized through supramolecular assembly, which show yellow emission with the near‐unity luminous efficiency under 450 nm excitation. Moreover, organic Cu(I) iodides exhibit bright X‐ray radioluminescence with a maximum light yield of 110200 photons per MeV. Subsequently, a paper‐based customizable large‐area flexible film is prepared in situ through “ancient cloth dyeing process”, and demonstrates its application in single‐component white light emitting diode and X‐ray imaging. Combined white light and X‐ray image fusion as well as multiangle imaging, the flexible film in the application of 3D image reconstruction is demonstrated. Furthermore, the flexible film can be recycled and reused in a N, N‐dimethylformamide solution while maintaining excellent stability. Considering that the flexible film can be degraded by microorganisms in natural soil into plant nutrients and participate in the carbon loop, it is conducive to achieving carbon neutrality.