Two-Dimensional Covalent Organic Framework (COF) Membranes Fabricated via the Assembly of Exfoliated COF Nanosheets.

Exceptionally homogeneous and ultrathin COF membranes were successfully fabricated using exfoliated COF nanosheets with uniform perforations as membrane building blocks. The COF membranes showed highly permeable performance due to the ultrafast molecular diffusion through the perforations of the COF nanosheets and the excellent thermal stability due to the robust covalent bonds in the framework.