Introduction of copper iodide fine particles into a poly(acrylic acid) matrixvia a complex of polymer–polyiodide ions

Abstract

In this study, an organic–inorganic nanocomposite material of cross-linked poly(acrylic acid) (PAA) doped with fine particles of copper iodide (CuI) was prepared. The preparation method of the composite involved the complexing of PAA film with polyiodide ions such as I₃⁻ and I₅⁻ by immersion in an iodine–potassium iodide (I₂–KI) aqueous solution, and then reaction with CuCl in aqueous hydrochloric acid, resulting in the in-situ formation of CuI fine particles within the PAA matrix. The crystal form of CuI in the composite was identified as γ-CuI using X-ray diffraction, and the amount of CuI could be varied by changing both the concentration of the I₂–KI solution and the frequency of performing the doping procedure to introduce CuI into the matrix. This preparation method, using polyiodide ions as a precursor, has an advantage in that a large amount of metal iodide, such as CuI, can be easily formed, and it is regarded as a unique method for the preparation of organic–inorganic composites.