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Publication Type : Journal Article
Thematic Areas : Nanosciences and Molecular Medicine
Publisher : Materials Research Bulletin
Source : Materials Research Bulletin, Volume 44, Number 3, p.714-717 (2009)
Keywords : A. Nanostructures, absorption, Absorption frequencies, Aqueous mediums, B. Chemical synthesis, Blue fluorescences, Chemical properties, Chemical reductions, Colloidal solutions, Coordination reactions, D. Luminescence, D. Optical properties, Fluorescence, Light emission, Luminescence, Metal ions, Nanoparticles, Nanostructures, Novel methods, Optical properties, Optically clears, particle size, Particle size distributions, Peak maximum, Polyethylene imines, Room temperatures, Silica, Silica substrates, Silver, Silver ions, Silver nano-particles, Silver nitrates, Silver particles, Spray coating techniques, Synthesis (chemical), TEM, transmission electron microscopy, Transmission electrons, Uv excitations, Uv-vis absorptions
Campus : Kochi
School : Center for Nanosciences
Center : Amrita Center for Nanosciences and Molecular Medicine Move, Nanosciences
Department : Nanosciences and Molecular Medicine
Year : 2009
Abstract : A novel method is reported here for the synthesis of optically clear and stable colloidal solutions of silver nanoparticles. According to size they show different colours depending upon their plasmonic absorption frequencies. The materials have been synthesized at room temperature by chemical reduction of silver ions (silver nitrate) coordinated with dendrigraft polymer, polyethyleneimine (PEI) using formaldehyde in aqueous medium. UV-vis absorption and transmission electron microscopy (TEM) studies show single-band absorption with peak maximum at 354 nm for ∼3 nm sized particles, whereas a side band at ∼400 nm was observed when the particle size increased to ∼20 nm. Highly narrow particle size distribution was observed in case of samples having ∼3 nm size silver particles and also the process of reduction could be completed within minutes. More interestingly, the 3-nm sized particles showed strong blue (474 nm) fluorescence under UV excitation. Thin films of all synthesized samples were prepared on silica substrate by fine spray coating technique.
Cite this Research Publication : M. Manoth, Koyakutty, M., Patra, M. K., Pandey, P., Vadera, S. R., and Kumar, N., “Dendrigraft Polymer-based Synthesis of Silver Nanoparticles Showing Bright Blue Fluorescence”, Materials Research Bulletin, vol. 44, pp. 714-717, 2009.