Accessing cationic zirconium phosphonate nanosheets for anion exchange applications

Abstract

Fabricating cationic extended framework material with better tolerance to harsh chemical and thermal treatments is highly solicited for several demanding applications. A facile route to imidazolium functionalized organophosphonic acid is devised. Subsequently, reaction of the imidazolium functionalized organophosphonic acid with ZrOCl2·8H2O give access to zirconium phosphonate nanosheets of thickness ∼ 10 nm. Covalently anchored dangling imidazolium groups are distributed uniformly over the zirconium phosphonate nanosheets and thereby leads to outstanding anion exchange capacity of the material. The stability of the cationic zirconium phosphonate material under acidic solution of pH 2, boiling water, alkaline solution of pH 12 and temperature upto 250 ˚C was explored by employing FT-IR, powder X-ray diffraction, TGA and 31P NMR studies.