Size-controlled gold nano-tetradecapodswith tunable optical and electromagnetic properties

Author : Kyeong Woo Choi, Shin Wook Kang, Do Youb Kim*, Sang Hyuk Im, Yangsun Park, Sang Woo Han* and O Ok Park*

Journal : Journal of Materials Chemistry C

Page : Vol. 4, No. 15, page 3063-3350(April, 2016)

[ABSTRACT]

The synthesis of novel branched Aunanocrystals with a well-defined and size-controllable dualistic structure, Aunano-tetradecapods, is presented. Using seed mediated growth and kineticallycontrolled reaction conditions, Au nano-tetradecapods with fourteen branchesgrown preferentially on the vertices of an Au rhombic dodecahedral core areobtained. The size of the branches is easily and readily controlled by simplyvarying the volume of HAuCl4 solution added or the reaction temperature, orboth. The localized surface plasmon resonance peak of the Au nano-tetradecapodscan be finely manipulated over a broad range of visible light through theselective tuning of their branch sizes. The enhanced and tunableelectromagnetic properties of the Au nano-tetradecapods are numericallyanalyzed using the finite difference time-domain method and they areexperimentally applied as effective surface enhanced Raman scatteringsubstrates as well. In addition, it is found that the branch/core size ratioderived from the dualistic structure is a critical parameter for determiningand controlling the properties of Au nano-tetradecapods.