Atomic intercalation of magnesium in mesoporous silica hollow spheres and its effect for removal of dyes

"Atomic" intercalation of magnesium (Mg) in mesoporous silica hollow spheres which are composed of ultrathin nanosheets with several nanometers in width has been achieved through a one-pot hydrothermal synthesis process. The highly dispersed state of Mg in the silica hollow spheres leads to the creation of more complicated shell morphology with higher surface area and larger pore volume than the silica hollow spheres without Mg. With the Mg intercalation, the structure may provide not only suitable spaces but also surface functions for the adsorption of various organic pollutants. In the removal of dyes (cationic or anionic) in the water solution, the Mg intercalated silica spheres showed much higher adsorption capacity in contrast to the silica hollow spheres without Mg. The removal efficiency can also be well maintained for repeated usage after the recovery. The work presents a new strategy to obtain silica spheres with highly homogeneously dispersed Mg and also may further promote the potential applications of hybrid silica materials in catalysis, drug delivery, and biosensing etc.