The preparation and electrochemical properties of nanostructured nickel hexacyanoruthenate deposited on multiwalled carbon nanotubes

A novel class of hybrid material was obtained by formation of nanostructured nickel hexacyanoruthenate (NiHCRu) on multiwalled carbon nanotubes (MWNTs). The method used in the electrode preparation gives reproducible deposits with well controlled quantity of the electroactive component. The composition of the formed layers was studied using XPS measurements while the morphology of the deposit was investigated with the aid of electron microscopy. TEM micrographs revealed detailed morphology of the nanostructrured material formed on the surface of the MWNTs. The obtained films were characterized by good stability and fast electron transfer reaction of the [Ru(CN)6]3−/[Ru(CN)6]4− system in the presence of Na+, NH4+, K+ and Rb+.The charge diffusion coefficient was estimated to be 3.4 × 10−8 cm2 s−1. Composite electrode exhibited a high affinity to Cs+ cations even in the presence of 104 excess in concentration of sodium ions. The results point that the nanocomposite film may be successfully used for removing of cesium ions from its aqueous solutions throughout an electrically switched ion exchange process.