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Quantitative structure–property relationship (QSPR) model has demonstrated that CO 2 /N 2 adsorptive selectivity of MOFs is dependent on Δ Q st 0 / φ (Δ Q st 0 is the difference of the isosteric heat of adsorption between the two gases and φ is the porosity of the MOF). Under the guidance of this model, three functionalized MOFs were designed by introducing double –NO 2 , –NH 2 , or –SO 3 H groups into each ligand of a platform MOF, [Zr 6 O 4 (OH) 8 (NDC) 6 ] n (Zr-NDC, NDC 2− = naphthalene-2,6-dicarboxylate). Molecular simulations were firstly applied to predict the gas adsorption properties of these materials, which show that CO 2 adsorption and separation capability can be greatly improved through incorporating these functional groups. Two analogues, [Zr 6 (O) 4 (OH) 8 (NDC-2NO 2 ) 6 ] n (Zr-NDC-2NO 2 ) and [Zr 6 (O) 4 (OH) 8 (NDC-2SO 3 H) 6 ] n (Zr-NDC-2SO 3 H) were then synthesized by using ligands 4,8-dinitronaphthalene-2,6-dicarboxylic acid (H 2 NDC-2NO 2 ) and 4,8-disulfonaphthalene-2,6-dicarboxylatlic acid (H 2 NDC-2SO 3 H), and checked experimentally for their CO 2 capture abilities. Compared with Zr-NDC, Zr-NDC-2NO 2 and Zr-NDC-2SO 3 H exhibit obviously enhanced CO 2 adsorption capacity and separation selectivity over N 2 , notwithstanding their pore sizes are reduced because of adding functional groups. Particularly, grafting two –SO 3 H groups in each ligand has led to a double gravimetric and triple volumetric increase of CO 2 adsorption capacity and a very high CO 2 /N 2 separation selectivity in Zr-NDC-2SO 3 H. Usually, the more functional groups in pores of a MOF are, the better their efficiency is. In these functionalized MOFs, the density of the functional groups is quite high, thus a huge impact on the gas adsorption property was achieved. These results also suggest that the QSPR model is a useful tool in designing MOFs with high performances for CO 2 capture. [ABSTRACT FROM AUTHOR]