The Ligand Exchanges of MOFs from Hydroxyl Groups to Methyl Groups for Better Stabilities

Abstract

The series of hollow and non-hollow metal-organic frameworks were developed via metal-organic polyhedron single crystals as sacrificial templates. In those series of MOFs, several organic ditopic linkers such as dabco, pz, and bipy (where dabco = 1,4-diazabicyclo[2.2.2]octane; pz = pyrazine; bipy = 4,4’-bipyridine) were used to synthesize the hollow and non-hollow MOF structures using the MOP single crystals of [Cu24(hip)24S24] (where hip = 5-hydroxyisophthalic acid). However, these MOFs are highly unstable at the atmospheric conditions since the building ligand has hydrophilic hydroxyl group attached; therefore, the ligand including those hydroxyl group is exchanged to the ligand with hydrophobic methyl group via postsynthetic method to improve the stabilities of those MOF series.