*2.2. Synthesis of CuI Nanostructured Materials*

CuI nanostructured materials were prepared by a modification in the method reported by Pramanik et al. [7]. In brief, a 6.0 mM potassium iodide solution was added to 6.0 mM of copper sulfate solution containing 5% (*w*/*v*) Arabic gum as a stabilizing agent. After that, a 30 µL concentration of hydrazine were dropwise added to the above mixture and the reaction was continued for 1 h at 60 ◦C. The nanostructured materials were collected by centrifugation at 4000 rpm for 10 min. These particles were washed several times with deionized water followed by centrifugation. The CuI NPs were recovered and dried at 60 ◦C in hot air oven for 6 h. These particles were fairly stable at room temperature for 1–2 weeks. They were stable in the sense that Cu did not oxidize and the composite did not aggregate (precipitate) during those 1–2 weeks. For the CuI@Ch composites, a 1.5% (*w*/*v*) solution of Medium Molecular Weight (MMW) chitosan was prepared in a 1% acetic acid solution. CuI nanostructured materials were prepared as powders and colloidal suspensions.
