Translator Disclaimer
7 October 2014 Functionalization of Ag nanoparticles using local hydrophilic pool segment designed on their particle surface
Author Affiliations +
The preparation of SiO2-coated Ag nanoparticles dispersible in various organic solvents has been achieved using a solgel reaction of tetraethylorthosilicate (TEOS), in the localized hydrophilic pool segments designed on Ag nanoparticle surfaces. First, oleylamine-capped core Ag nanoparticles were synthesized, followed by ligand exchange with polyethyleneimine (PEI) and further adsorption of an anionic surfactant comprising hydrophilic polyethylene glycol (PEG) chains and hydrophobic alkyl chains, which has previously been reported to improve the stability of nanoparticles in various solvents. Then, a reaction of TEOS with the localized hydrophilic PEI layer on the Ag nanoparticles’ surface was conducted by stirring a toluene/TEOS solution of surface-modified Ag nanoparticles at various temperatures. It was found that a SiO2 layer was successfully formed on Ag nanoparticles when the reaction temperature was increased to 60 °C. It was also found, however, that at this elevated temperature, the primary particle size of Ag nanoparticles increased to several tens of nm, attributable to the dissolution and re-reduction of Ag+. Because the surface modifier, PEI and anionic surfactant all remained on the nanoparticle surface during the SiO2 coating process, the prepared SiO2-coated Ag nanoparticles were found to be dispersible in various organic solvents near to their primary particle size.
© (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Motoyuki Iijima, Aki Kurumiya, Junki Esashi, Hayato Miyazaki, and Hidehiro Kamiya "Functionalization of Ag nanoparticles using local hydrophilic pool segment designed on their particle surface", Proc. SPIE 9176, Solar Hydrogen and Nanotechnology IX, 91760I (7 October 2014);

Back to Top