Taking <i>C</i>-phenylresorcin[4]arene
(RN4) as a model building block, we fabricated a series of porous organic polymers
(POPs: RN4-OH, RN4-Az-OH, and RN4-F) where the surface area was enhanced up to ~8
folds (1229 m<sup>2 </sup>g<sup>-1</sup>) than that of the pristine cavitand
(156 m<sup>2 </sup>g<sup>-1</sup>). The advantage of connecting the 0D porous cavitands
was demonstrated through three environmentally relevant applications, namely, catalytic
conversion of CO<sub>2</sub> to value-added products, selective gas (CO<sub>2</sub>,
H<sub>2</sub>) uptake, and the charge-specific size-selective separation of
organic micropollutants from water. In all the cases, RN4-derived POPs have
outperformed the pristine 0D porous macrocyclic cavitand.