synthesis and interface boundary characteristics of gold/cobalt janus nanoparticles
Name: Kyungah Seo
Grad Year: 2018
Janus particles consist of two nanoparticles assembled into one by a close contact. The interface between the two nanoparticles can be used as a link for electron transfer across them, which introduces unique catalytic, optical, and magnetic properties, that otherwise are not accomplished in the individual nanoparticles. It has been previously shown that the connection of magnetic nanoparticles (Fe2O3) to noble metals (Au, Pt) results in a red shift of the surface plasmon of the metal, which increases the magnetization of the magnetic nanoparticles. However, the mechanism behind this effect is still not fully explained. In this study, plasmonic/magnetic (Au/Co) bimetallic Janus nanoparticles were prepared to determine the effect of surface stability and atomic diffusion on the interface between gold and cobalt. Various synthesis conditions were used for preparation of Janus nanoparticles to verify the changes in morphology, plasmonic, and the interface between Au and Co. The particles were synthesized by growing Co over the pre-synthesized Au seeds via thermal decomposition of Co2(CO)8 in organic solutions. The particles were prepared in several different solutions of varying polarity, including 1-octadecene, diphenyl ether, and benzyl ether, as well as using various amounts of surfactant/reducing agents, different reaction temperatures and reaction times, to study the effect of cobalt growth on the gold seeds. After the preparation, 5nm/20nm (Au/Co) particles were observed via Transmission electron microscopy (TEM), X-ray diffraction (XRD), and UV-vis spectroscopy to characterize the sizes, shapes, morphologies and plasmonic characteristics of the synthesized particles.
Industry Application Area(s)
Aerospace, Defense, Security | Life Sciences/Medical Devices & Instruments | Materials