Epitaxial Growth of Hetero‐Ln‐MOF Hierarchical Single Crystals for Domain‐ and Orientation‐Controlled Multicolor Luminescence 3D Coding Capability

Core–shell or striped heteroatomic lanthanide metal–organic framework hierarchical single crystals were obtained by liquid‐phase anisotropic epitaxial growth, maintaining identical periodic organization while simultaneously exhibiting spatially segregated structure. Different types of domain and orientation‐controlled multicolor photophysical models are presented, which show either visually distinguishable or visible/near infrared (NIR) emissive colors. This provides a new bottom‐up strategy toward the design of hierarchical molecular systems, offering high‐throughput and multiplexed luminescence color tunability and readability. The unique capability of combining spectroscopic coding with 3D (three‐dimensional) microscale spatial coding is established, providing potential applications in anti‐counterfeiting, color barcoding, and other types of integrated and miniaturized optoelectronic materials and devices.