The introduction of a base component to porous organic salts and their CO 2 storage capability

Porous organic salts ( POSs ) are constructed by charge-assisted hydrogen bonding between amino and sulfonic groups, and can be used to design a variety of porous structures based on molecular design. In particular, triphenylmethylamine ( TPMA ) and aromatic sulfonic acids form robust POSs with a rigid diamond structure ( d -POSs ). In this study, by replacing one of the three phenyl rings of TPMA with a pyrimidine ring, we succeeded in constructing a d -POS with high porosity (43.8%) and with a base component (pyrimidine) on the void surface. In addition, the weak basicity of the pyrimidine did not interfere with the formation of d -POSs . This d -POS adsorbed CO 2 over the primary air components (N 2 and O 2 ) and also exhibited CO 2 storage capability: It retained CO 2 at a relatively low pressure of P e / P 0 = 0.05, and readily desorbed CO 2 below P e / P 0 = 0.05.