Facile synthesis of highly luminescent nanowires of a terbium-based metal-organic framework by an ultrasonic-assisted method and their application as a luminescent probe for selective sensing of organoamines

摘要

In this paper, we report on a facile and environmentally friendly large-scale synthesis of metal-organic framework (MOF) nanowires by using an ultrasonic method without the introduction of any seeds, polymers, or surfactants. Highly luminescent nanowires of a one-dimensional terbium benzenetricarboxylate MOF, [Tb(1,3,5-btc)(H2O)6]_n (l,3,5-btc = benzene-T,3,5-tricarboxylate), with an average diameter of 50 nm and lengths of up to a few micrometers can be easily obtained in a relatively high yield under ultrasound irradiation at 70 °C and under atmospheric pressure. The structure and morphology of the as-synthesized MOF nanowires were characterized by powder X-ray diffractometry (PXRD) and field emmision scanning electron microscopy (FE-SEM), respectively. The (Tb(l,3,5-btc)(H2O)6]n nanowires obtained show strong luminescence emission at 548 and 492 nm, and exhibit high selectivity for sensing of aromatic amines, such as aniline and p-phenylenediamine, in comparison with alkylamines (e.g. methylamine, ethylamine, n-propylamine, n-butylamine and triethylamine). Such a significantly selective luminescence quenching effect of [Tb(l,3,5-btc) (H2O)6]_n nanowires for aromatic amines makes the nanostructured Tb-MOF-based sensing materials potential for sensing of aromatic amines in a mixture solution of organoamines.