Silabenzene Incorporated Covalent Organic Frameworks

TL;DR

This paper reports the synthesis and detailed characterization of silicon-incorporated covalent organic frameworks using silabenzene units, revealing structural transformations and potential for new applications in organosilicon chemistry.

Contribution

It introduces a novel method for incorporating silabenzene into COFs, expanding structural diversity and understanding of their chemical properties.

Findings

Silabenzene units successfully incorporated into COFs.

C4Si2 rings can transform into C4Si pentagonal rings upon annealing.

Detailed structural and chemical analysis of Si-COFs conducted.

Abstract

Covalent organic frameworks (COFs) are a promising material for various applications such as gas storage/separation, catalysis, and energy storage, besides offering a confined space for chemical reaction. The introduction of unconventional elements into their frame structures and expanding their structural scope remains a major challenge in COF chemistry. Here, we present syntheses of two-dimensional and liner COFs substructures linked with 1,4-disilabenzene (C4Si2) by co-depositing silicon atoms and bromo-substituted poly aromatic hydrocarbons on Au(111). A combination of high-resolution scanning tunneling microscopy, photoelectron spectroscopy and density functional theory calculations reveal the detailed structures of the Si-incorporated COF, as well as its chemical properties. We find that each Si in a hexagonal C4Si2 ring is terminated by one Br atom. Furthermore, the C4Si2 ring can be transformed to the C4Si pentagonal ring by annealing. Silabenzene incorporated COFs may open up new possibilities in organosilicon chemistry and a wide range of practical applications.