Functionalized Mesoporous Silica for Highly Selective Sensing of Iron Ion in Water.

In this study, we examined the highly selective sensing of Fe ions in water using metal complex-functionalized mesoporous silica materials. Metal complex-functionalized mesoporous silica materials were synthesized on the mesoporous surface of SBA-15 via complexation process between Eu and aminosilane groups. Mesoporous silica, SBA-15, and the Eu-complex functionalized SBA-15 were characterized using X-ray diffraction (XRD), transmittance electron microscopy (TEM), nitrogen sorption behavior, and Fourier transform infrared (FTIR) spectroscopy. The sensing behavior of the Eu-complex functionalized SBA-15 was studied using various metal ions (Fe, Cu, Cr, Co, Hg, Pb, and Zn) aqueous solutions. Photoluminescence intensity ( = 612 nm) of the Eu-complex functionalized SBA-15 was dependent on the different interactions between metal ions and Eu-complexes. Photoluminescence intensity at = 612 nm of the Eu-complex functionalized SBA-15 decreased to near zero and proved the highly selective sensing effect of Fe. Therefore, the Eu-complex functionalized SBA-15 can be considered an excellent candidate for sensing iron ions in water.