Improving the Stability and Gas Adsorption Performance of Acylamide Group Functionalized Zinc Metal–Organic Frameworks through Coordination Group Optimization

In order to elucidate the effect of the structure on stability and gas adsorption performance, three porous Zn­(II) metal–organic frameworks, NKU<b>-106</b>, NKU<b>-107</b>, and NKU<b>-108</b>, have been constructed. NKU-<b>106</b> and NKU-<b>107</b> assembled from acylamide functionalized tetracarboxylate ligand exhibit low stability and thereby poor gas adsorption ability. However, when one isophthalate moiety of the tetracarboxylate ligand is replaced with a pyrazole group, and the resulting NKU-<b>108</b> shows improved thermal and chemical stability as well as good adsorption capacities with respect to CO₂ and C₂ hydrocarbons. This result demonstrates that coordination group optimization is an effective strategy to improve the stability and gas adsorption properties of metal–organic frameworks (MOFs) and thus provides very valuable information for future design and synthesis of porous MOFs for practical application