Silicate-based multifunctional nanostructured materials with magnetite and Prussian blue: application to cesium uptake

Multifunctional nanostructured materials with superparamagnetic and adsorbent properties towards cesium ions were developed by a simple procedure consisting of the one-pot synthesis of magnetite and Prussian blue nanoparticles (NPs) in the presence of a porous inorganic solid that acts as a support or nanoplatform simultaneously assembling both types of NPs. Sepiolite, a hydrated magnesium silicate with fibrous morphology, microporosity, large specific surface area and bearing hydroxyl groups in its external surface, was here chosen as the nanoplatform supporting the in situ synthesized NPs, although this methodology was also successfully proved using other inorganic solids like silica gel. The efficacy of the resulting materials in the adsorption of cesium ions from aqueous media, even in the presence of a high concentration of sodium chloride, would allow their application in the removal of radioactive cesium-137 with the advantage of an easy and quick recovery of the pollutant-loaded adsorbents by means of a magnet.