Iron Intercalation in Covalent-Organic Frameworks: A Promising Approach for Semiconductors

TL;DR

This study uses advanced computational methods to design and analyze Fe-intercalated covalent-organic frameworks, revealing their potential as tunable semiconductors with improved electronic properties.

Contribution

It introduces a novel computational approach to intercalate Fe atoms into COFs, demonstrating their promising semiconductor behavior and potential for controlled material design.

Findings

Fe intercalation tunes electronic properties of COFs

Intercalated COFs exhibit promising semiconductor characteristics

Fe's d-electrons enhance electronic performance

Abstract

Covalent-organic frameworks (COFs) are intriguing platforms for designing functional molecular materials. Here, we present a computational study based on van der Waals dispersion-corrected hybrid density functional theory (DFT-D) to design boroxine-linked and triazine-linked COFs intercalated with Fe. Keeping the original $P-6m2$ symmetry of the pristine COF (COF-Fe-0), we have computationally designed seven new COFs by intercalating Fe atoms between two organic layers. The equilibrium structures and electronic properties of both the pristine and Fe-intercalated COF materials are investigated here. We predict that the electronic properties of COFs can be fine tuned by adding Fe atoms between two organic layers in their structures. Our calculations show that these new intercalated-COFs are promising semiconductors. The effect of Fe atoms on the electronic band structures and density of states (DOSs) has also been investigated using the aforementioned DFT-D method. The contribution of the $d$-subshell electron density of the Fe atoms plays an important role in improving the semiconductor properties of these new materials. These intercalated-COFs provide a new strategy to create semi-conducting materials within a rigid porous network in a highly controlled and predictable manner.