Cation‐Controlled Aqueous Dispersions of Alginic‐Acid‐Wrapped Multi‐Walled Carbon Nanotubes

It′s a wrap! Alginic acid can efficiently solubilize multi-walled carbon nanotubes (MWCNTs) in aqueous solution (see figure). The addition of cations to the alginic-acid-wrapped MWCNTs results in their precipitation from aqueous solution. However, subsequent treatment with EDTA selectively redispersed those MWCNTs that were precipitated with Zn2+, Ni2+, Co2+, Pb2+, La3+, and Eu3+ ions in water.