Terpyridine-Functionalized NanoSiO2 Multi-Dentate Linkers: Preparation, Characterization and Luminescent Properties of Their Metal–Organic Hybrid Materials

Abstract

Terpyridine- (TPy-) functionalized silica nanolinkers (nanoSiO2–TPy) have been prepared and used as nanoscale multidentate ligands to coordinate with the transition metal ions (Mn+ = Zn2+, Fe2+, Tb3+ and Eu3+) for producing luminescent metalated organic–inorganic nanoSiO2–TPyM hybrid materials. Thermogravimetric analysis has revealed that the covalently attached organic species in the nanoSiO2–TPy linkers were about 10% in weight. After they were functionalized with the layers of TPy or TPyM, the as-prepared nanoSiO2–TPy linkers and nanoSiO2–TPyM hybrids formed aggregates more easily due to an increase of internanoparticle interactions. The ζ-potential of the nanoSiO2–TPy linkers was about 34.6 mV, which increased to 55 to 60 mV for the nanoSiO2–TPyM hybrids in the poly(ethylene glycol) 200 (PEG 200) solutions. Under UV radiation, the nanoSiO2–TPy linkers gave off an emission at about 366 nm (monomer of the linkers) in the PEG 200 solutions with the concentrations below 0.5 mg/mL, which shifted to 374 nm ...