Magnetically separable Prussian blue analogue Mn3[Co(CN)6]2•nH2O porous nanocubes as excellent absorbents for heavy metal ions

The application of Prussian blue analogue (PBA) Mn-3[Co(CN)(6)](2)center dot nH(2)O porous nanocubes as absorbents for heavy metal ions has been demonstrated. The result indicates that Mn-3[Co(CN)(6)](2)center dot nH(2)O porous nanocubes with average diameter of 240 nm possess excellent adsorption efficiency for Pb2+ ions (94.21% at initial Pb2+ concentration of 10 mg L-1). Moreover, Mn-3[Co(CN)(6)](2)center dot nH(2)O porous nanocubes can also show high adsorption efficiency on heavy metal ions even in a strong acidic solution due to its chemical stability. Notably, an external magnet could be used to accelerate the separation of Mn-3[Co(CN)(6)](2)center dot nH(2)O from the treated solution. It is suggested that the high adsorption efficiency may derive from the large surface area, M-3(II)[M-III(CN)(6)](2)center dot nH(2)O porous framework structure and affinity between polarizable pi-electron clouds of the cyanide bridges and heavy metals ions.