  Porous polymeric covalent organic frameworks (COFs) have been under intense
synthetic investigation with over 100 unique structural motifs known. In order
to realize the true potential of these materials, converting the powders into
thin films with strict control of thickness and morphology is necessary and
accomplished through techniques including interfacial synthesis, chemical
exfoliation and mechanical delamination. Recent progress in the construction
and tailored properties of thin film COFs are highlighted in this review,
addressing mechanical properties as well as application-focused properties in
filtration, electronics, sensors, electrochemical, magnetics, optoelectronics
and beyond. Additionally, heterogeneous integration of these thin films with
other inorganic and organic materials is discussed, revealing exciting
opportunities to integrate COF thin films with other state of the art material
and device systems.
