Facet‐Selective Nucleation Control for Constructing Multi‐Dimensional MOFs Heterostructures

Metal-organic framework (MOF) heterostructures featuring tunable morphologies and compositions have shown great promise for applications in high-throughput sensing, anti-counterfeiting, and information encryption. Nevertheless, the precise engineering of heterogeneous architectures with multi-dimensional building units remains challenging, primarily hindered by an insufficient understanding of the growth dynamics between modules of different dimensionality. Here, we demonstrate a facet-selective epitaxial growth approach for architecting spatially defined dimensional heterostructures via crystalline plane-selective reactivity control. The intrinsically higher surface energy at the tips of 1D microrods facilitates the nucleation of 2D modules on the terminal facets, thereby yielding dumbbell-like heterostructures. Conversely, by selectively enhancing the reaction activity on the body regions of the 1D templates, preferential nucleation and growth at the central areas over the tips were effectively achieved, which enables the controlled formation of periodic modular architectures through systematic regulation of surface energies. The facet-selective epitaxial growth paradigm establishes a pathway for synthesizing hierarchical dimensional heterostructures with tailored architectures, which show great promise for applications in advanced optoelectronics, anti-counterfeiting systems, and information encryption technologies.