Highlights

• This paper uses invisible, printable lead-based MOFs as precursors that can be converted into bright perovskite nanocrystals by a halide trigger.
• The approach enables confidential information to remain hidden under normal viewing and then be decrypted by chemically generating luminescent perovskite nanocrystals.
• The luminescence can be switched off and recovered, offering a reversible encryption/decryption platform.

Summary

This study shows how perovskite chemistry can be used not only for displays but also for smart security materials. Traditional fluorescent inks can often be detected under UV light, which limits their value for confidential information protection. In this work, the recorded MOF pattern is initially invisible and non-fluorescent. When exposed to a halide salt trigger, the MOF converts into luminescent perovskite nanocrystals, revealing the hidden information. The innovation is to treat perovskite formation itself as the decryption process. This paper broadens the cluster by demonstrating that nanocrystal stabilization and transformation chemistry can support information storage, encryption, and anti-counterfeiting applications.

Citation: C. Zhang et al., “Conversion of invisible metal-organic frameworks to luminescent perovskite nanocrystals for confidential information encryption and decryption,” Nature Communications, vol. 8, article 1138, 2017, doi: 10.1038/s41467-017-01248-2.