Ion-imprinted mesoporous silica hybrids for selective recognition of target metal ions

• A novel ion-imprinted ligand bearing periodic mesoporous organosilica was obtained.
• The imprinted metal template was easily leached out from the PMO during an acid treatment.
• The selective efficiency of Co2+ ions on the PMO was 10.1 for Cu2+.

A novel ion-imprinted functional ligand derivative bearing periodic mesoporous organosilica (IIPMO) was obtained using a sol–gel process from a chemically synthesized organopolysilane precursor with a metal template (Co2+ ion) imprinted ligand centre with tetraethylorthosilicate (TEOS) and cetyltrimethylammoniumbromide (CTAB) as a structural directing surfactant under basic conditions. The imprinted metal template was easily leached out from the hybrid materials during an acid treatment, which resulted in a template-free ion-imprinted network in the PMO pore wall framework with an unaltered particle size and morphology. The ion-imprinted hybrid PMO materials were characterized by X-ray diffraction, Fourier transform-infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, solid-state 29Si and 13C cross polarization magic angle spinning nuclear magnetic resonance spectroscopy, N2 adsorption–desorption analysis and elemental analysis. Furthermore, the removal of the imprinted metal template was confirmed by inductively coupled plasma-atomic emission spectroscopy. The selective rebinding ability of the template ions on the ion-imprinted PMO hybrid adsorbents was examined using a cobalt nitrate solution. The rebinding results showed that the selective efficiency of Co2+ ions on the IIPMOs were 10.1, 7.4 and 9.3 for Cu2+, Cd2+ and Zn2+, respectively.

A novel ion-imprinted functional ligand derivative bearing periodic mesoporous organosilica (IIPMO) was obtained via sol-gel process from a chemically synthesized organopolysilane precursor having a metal template (Co2+ ion) imprinted ligand center with tetraethylorthosilicate (TEOS) and cetyltrimethylammoniumbromide (CTAB) as a structural directing surfactant under basic conditions.Figure optionsDownload as PowerPoint slide