Near-infrared/visible-emitting nanosilica modified with silylated Ru(II) and Ln(III) complexes

Abstract

Three luminescent silica-based nanohybrids were fabricated by grafting of silylated Ru(II)andNd/Yb(III)complexes onto mesoporous silica nanoparticles obtained by microemulsion method.The prepared nanohybrids were characterized by Fourier transform-Raman spectroscopy, solidstate-nuclear magnetic resonance, high resolution-transmission electron microscopy andscanning and transmission electron microscopy techniques. The chemical integrity and thegrafting of all complexes inside MSNs nanopores as well as a good distribution of metalcomplexes onto MSNs surface were achieved for all nanohybrids. Photophysical results revealedthat by monitoring the excitation on Ru(II)moieties from SiO2–RuNd and SiO2–RuYb nanohybrids, the sensitization of NIR-emitting Nd/Yb(III)ions were successfully detected viaenergy transfer processes. Energy transfer rates(kEnT)of 0.20×107and 0.11×107s−1 and efficiencies of energy transfer(ηEnT)of 40% and 27.5% were obtained for SiO2–RuNd and SiO2–RuYb nanohybrids, respectively. These results confirm the preparation of promising dual(near-infrared/visible)-emitting silica-based nanohybrids as new nanotools for applications asnanosensores and nanomarkers.