Chemistry Reference
In-Depth Information
2.3.4 Structure of Crystalline POFs
Generally speaking, to afford 2D COFs with designed topology and pore structure,
2D blocks are the fundamental elements. Besides the above-mentioned reaction, most
of the 2D COFs could be formed in terms of 2D-
C
2
+
2D-
C
3
, 2D-
C
3
+
2D-
C
3
, and
2D-
C
2
+
2D-
C
4
. Figure
2.11
lists the representative building blocks with different
geometries to design 2D COFs.
For porous materials, pore size is one of the most important features. The pore
size of the resulted COF materials could be tuned through adjusting the length of
monomers or decorating additional groups into the building units. Figures
2.12
and
2.13
indicate that the factors lead to the change in pore sizes [
9
,
10
].
To obtain 3D COFs, one of the monomers must be 3D block, and the types
of combinations are 3D-T4
T
4
+
3D-
T
4
, 3D-
T
4
+
2D-
C
2
, and 3D-
T
4
+
2D-
C
3
.
Figure
2.14
shows the employed 3D-T4
T
4
monomers, such as tetraphenyl methane
and tetraphenyl silicon derivatives, adamantane derivative, etc.
Fig. 2.11
The representative building blocks with different geometries to design 2D COFs
