0D Cu–I clusters have attracted significant attention because of their structural diversity and ability to create multiple electron-hole-pair recombination centers, positioning them as promising candidates for high-performance luminescent devices. In contrast, 1D Cu–I coordination polymers, which serve as analogs to their 0D counterparts, share similar traits, such as X-ray absorption efficiency, structural diversity, and solution processability, while also offering enhanced photostability. Despite these advantageous characteristics, the potential of 1D Cu–I coordination polymers remains largely underexplored, primarily because of their low radiative processes, which limit their applications in light conversion.

In this study, we propose a chemical approach to enhancing the optical properties and light-conversion capabilities of 0D Cu–I clusters by employing a ligand halogen engineering strategy. This method involves incorporating halogen atoms into the ligands, leading to improved structural rigidity and stability. Our research not only introduces a technique for maximizing the performance of X-ray imaging scintillators but also emphasizes the potential of 1D Cu–I coordination polymers to advance medical diagnostics and security screening technologies.