Macroscopic alignment of metal–organic framework crystals in specific crystallographic orientations

Abstract

This review explores synthetic strategies for macroscopic aligned MOFs, enhancing properties without structural designs or post-synthetic reactions.

Improved optical quality of heteroepitaxially grown metal–organic framework thin films by modulating the crystal growth

“…Another significant challenge for MOF-based device applications is controlling the alignment of MOF crystals in both the out-of-plane and in-plane directions to maximise device performance. 13,19–22 Consequently, we developed a fabrication process for MOF thin films with both out-of-plane and in-plane orientations via the epitaxial growth of MOF crystals on preformed copper hydroxide substrates, 23 which can be converted to MOFs in relatively short and mild reactions. Three-dimensional (3D)-oriented MOF films and multilayered MOF (MOF-on-MOF) thin films 24,25 have demonstrated unique in-plane anisotropic optical 26,27 and electrical 28 properties on a macroscopic scale (measured in centimetres), owing to the macroscopic alignment of well-defined micropores and frameworks of MOFs, which could not be achieved by MOF films with only one-dimensional (1D) and out-of-plane orientations.…”