By means of a mixed-ligand strategy, a novel bi-functional metal-organic framework, [H2N(CH3)2]·Zn(NDC)(atz)·H2O (NDC = 2,6-naphthalenedicarboxylic acid, Hatz = 1H-tetrazol-5-amine), was synthesized, which displays a three-dimensional two-fold interpenetrated framework. Owing to the introduction of two different functional organic ligands, this complex exhibits bi-functional properties, i.e., s...