From microcrystalline to nanosized α-zirconium phosphate: Synthetic approaches and applications of an old material with a bright future

The present review aims to retrace the main stages of the development of the chemistry of α-type zirconium monohydrogen phosphate layered compound (α-ZrP) from the earlier studies on its structure up to date, gathering the most significant papers on synthetic approaches and applications. The review provides, for the first time, a rational description of the procedures for the synthesis of α-ZrP and for the control of the particle morphology, especially their aspect ratio. Two sections are dedicated to the synthesis of α-ZrP, one dealing with the traditional approaches based on the use of Zr(IV) water soluble complexes and on the crystallization of amorphous precipitates, the other one focused on alternative synthetic methods. Attention is also focused on the synthesis of ZrP organic derivatives, among them surface modified ZrP compounds, phosphonates and organophosphates. Finally, the last section reviews the most representative applications of α-ZrP and its organic derivatives in the field of polymer nanocomposites and biomaterials.