(A) Schematic illustration of the multiblock MOF structure fabricated by the epitaxial growth process of BTC and different Ln ions. (B₁)–(B₃) PM images of the Ln-BTC triblock heterostructures under UV irradiation. Scale bars are 10 μm. (C) Schematic illustration of penta-block superstructures fabricated by further epitaxial growth. (D) PL image of the 1D penta-block superstructures. Scale bar is 5 μm. (E), (F) The magnified PM image and corresponding barcode of the penta-block superstructures. Scale bar is 5 μm (Reproduced from Ref. [121]. Copyright©2019, Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim). (G) Chemical structures of the Ir donor([Ir(ppy)₂(pzpy)]⁺) and the Ru acceptor([Ru(bpy)₃]²⁺) (counteranions are PF⁶⁻). (H)–(I) Schematic representation of the three-stage growth process for preparing Ir(III) and Ru(II) multiblock nanorods. (J₁)–(J₂) Fluorescence microscopy images of multiblock nanorods doped with (J₁) 0.5%, (J₂) 1%, Ru acceptor under UV irradiation. Scale bar is 20 mm (Reproduced from Ref. [122]. Copyright©2018, American Chemical Society). (K) Longitudinal epitaxial growth strategy for the preparation of organic multi-block microwires through a continuous self-assembly process. (L₁), (L₂) FM images of organic quintuple-block microwires prepared with the acceptor molecular content η_TFP of 6%. The scale bars of (L₁) and (L₂) are 20 and 5 μm, respectively. (M) TEM image of one typical organic triple-block microwire. Scale bar is 5 μm. The upper right and lower right insets are SAED patterns collected from the central part (marked by red grid lines) and end parts (marked by green grid lines) of triblock microwires, respectively. (N) Molecular arrangement and orientation of BTP and BTB crystals at the junction of multiblock structure (Reproduced from Ref. [123]. Copyright©2021, The Author(s)).