Controlled production of ZnO nanoparticles from zinc glycerolate in a sol-gel silica matrix.
The controlled production of ZnO nanoparticles within an amorphous silica matrix is achieved using a new methodology consisting of four stages. First, precursor zinc glycerolate nanoparticles are produced within reversed micelles of glycerol in heptane stabilized by the surfactant Aerosol-OT (bis-ethylhexyl sodium sulfosuccinate, AOT). The surface of these nanoparticles is then modified by exchanging AOT with bis-trimethoxysilyl-ethane (BTME). The surface-modified nanoparticles are copolymerized with tetramethoxysilane (TMOS) to provide a composite silica material, in which the nanoparticles are apparently dissolved, producing a uniform distribution of zinc in the silica matrix. Finally, the conversion of zinc to ZnO is achieved by heating the material at 700 degrees C, leading to a uniform dispersion of very small (<10 nm) ZnO particles within the amorphous matrix. The fluorescence spectrum of the ZnO particles within the matrix is blue-shifted, as expected from the strong quantum confinement achieved. The properties of the system at all stages in this synthetic process are monitored using TEM, XRD, fluorescence and FT-IR spectroscopy. Glycerol forms complexes with many metal ions, so the present procedure may be generalized to provide uniform distributions of metal ions and subsequently metal oxide nanoparticles in amorphous silica.
Moleski
Rodoula
R
Department of Chemistry, University of Cyprus, P.O. Box 20537, 1678 Nicosia, Cyprus.
Leontidis
Epameinondas
E
Krumeich
Frank
F
D004655:Emulsions / Q000138:chemical synthesis / Q000737:chemistry; D005782:Gels / Q000737:chemistry; D005990:Glycerol / Q000737:chemistry*; D008823:Micelles; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D012822:Silicon Dioxide / Q000737:chemistry*; D013499:Surface Properties; D015032:Zinc / Q000737:chemistry*; D015034:Zinc Oxide / Q000138:chemical synthesis* / Q000737:chemistry
D004655:Emulsions; D005782:Gels; D008823:Micelles; D012822:Silicon Dioxide; D015032:Zinc; D005990:Glycerol; D015034:Zinc Oxide