Coassembly of Complementary Polyhedral Metal-Organic Framework Particles into Binary Ordered Superstructures

Abstract

Here we report the formation of a 3D NaCl-type binary porous superstructure via coassembly of two colloidal polyhedral metal-organic framework (MOF) particles having complementary sizes, shapes, and charges. We employed a polymeric-attenuated Coulombic self-assembly approach, which also facilitated the coassembly of these MOF particles with spherical polystyrene particles to form 2D binary superstructures. Our results pave the way for using MOFs to create sophisticated superstructures comprising particles of various sizes, shapes, porosities, and chemical compositions.

Figure 1

(a) Schematics and FESEM images of the coassembly of C-ZIF-8 particles and PS particles into 2D binary superstructures. (b, c) Schematic and FESEM images of the superstructure showing C-ZIF-8 particles assembled along two distinct orientations, highlighted in red and blue. (d, e) FESEM images of the superstructure under different magnifications. (f–i) Schematics and FESEM images of a 45°-tilted 2D binary superstructure viewed from different angles. (j, k) Schematic and FESEM image of a 45°-tilted 2D binary superstructure made of C-ZIF-8 particles (edge size: 196 ± 12 nm). Scale bars in (a), (c), (g), (i), (k): 1 μm. Scale bars in insets: (a, b) 200 nm; (d) 10 μm; (e) 5 μm.

Figure 2

Schematics and FESEM images of (a) C-ZIF-8 and TRD-ZIF-8 particles and (b, c) the fcc NaCl-type porous binary superstructure, showing its 3D character. Scale bars: (a–c) 1 μm; (insets of a) 200 nm.

Figure 3

(a–c) FESEM images of a 45°-tilted NaCl-type porous binary superstructure showing (a) long-range order and (b, c) magnified views. (d–g) Schematic and FESEM images of top views of the NaCl-type porous binary superstructure. (h) PXRD patterns of disordered C-ZIF-8 particles (black), TRD-ZIF-8 particles (red), and the ordered binary superstructure (blue). Scale bars: (a) 10 μm; (d) 2 μm; (b,c,f) 1 μm; (g) 400 nm.