1 research outputs found
Oligothiophene-Bridged Conjugated Covalent Organic Frameworks
Two-dimensional covalent organic
frameworks (2D-COFs) are crystalline,
porous materials comprising aligned columns of π-stacked building
blocks. With a view toward the application of these materials in organic
electronics and optoelectronics, the construction of oligothiophene-based
COFs would be highly desirable. The realization of such materials,
however, has remained a challenge, in particular with respect to laterally
conjugated imine-linked COFs. We have developed a new building block
design employing an asymmetric modification on an otherwise symmetric
backbone that allows us to construct a series of highly crystalline
quaterthiophene-derived COFs with tunable electronic properties. Studying
the optical response of these materials, we have observed for the
first time the formation of a charge transfer state between the COF
subunits across the imine bond. We believe that our new building block
design provides a general strategy for the construction of well-ordered
COFs from various extended building blocks, thus greatly expanding
the range of applicable molecules