The Growth Mechanism of a Conductive MOF Thin Film in Spray-based Layer-by-layer Liquid Phase Epitaxy

The layer-by-layer liquid-phase epitaxy (LBL-LPE) method is widely used in preparing metal-organic framework (MOF) thin films with the merits of controlling thickness and out-of-plane orientation for superior performances in applications. The LBL-LPE growth mechanism related to the grain boundary, structure defect, and orientation is critical but very challenging to study. In this work, a novel in-plane self-limiting and self-repairing thin-film growth mechanism is demonstrated by the combination study of the grain boundary, structure defect, and orientation of Cu-3(HHTP)(2)-xC thin film via microscopic analysis techniques and electrical measurements. This mechanism results a desired high-quality MOF thin film with preferred in-plane orientations at its bottom for the first time and is very helpful for optimizing the LBL-LPE method, understanding the growth cycle-dependent properties of MOF thin film, and inspiring the investigations of the biomimetic self-repairing materials.

Automated summary

This study demonstrates a novel self-limiting and self-repairing thin-film growth mechanism, which achieves high-quality MOF thin films with preferred in-plane orientations at the bottom. This is very helpful for optimizing the LBL-LPE method, understanding the growth cycle-dependent properties of MOF thin films, and inspiring investigations of biomimetic self-repairing materials.