【ACS Applied Materials & Interfaces】Engineering Gold Nanoparticles in Compass Shape with Broadly Tunable Plasmon Resonances and High-Performance SERS
writer：Huang, Youju*; Dai, Liwei; Song, Liping; Zhang, Lei; Rong, Yun; Zhang, Jiawei; Nie*, Zhihong; Chen, Tao*
keywords：Gold Nanoparticles
source：期刊
specific source：ACS Applied Materials & Interfaces, 2016, Accepted Manuscript
Issue time：2016年
We present the uniform and high-yield synthesis of a novel gold nanostructure of compass shape composed of a Au sphere at the central and two gradually thinning conical tips at opposed poles. The Au compass shapes were synthesized via a seed-mediated growth approach employing a binary mixture of cetyltrimethylammonium bromide (CTAB) and sodium oleate (NaOL) as the structure-directing agent. Under condition of single
surfactant (CTAB), the spherical seeds tend to growth into bigger spherical
Au nanoparticles (NPs); while the spherical seeds favor the formation of Au compass
shaped NPs by using two mixed surfactants (CTAB/NaOL). The reaction kinetics
clearly shows growth mechanism of Au compass shaped NPs. Interestingly, due to their
anisotropic structure, Au compass shaped NPs show two distinctive plasmonic resonances,
similar to those from Au nanorods (AuNRs). Particularly, the longitudinal surface plasmon resonances of Au compass shaped NPs exhibits a broadly tunable range from 600 to 865 nm. In addition, the obtained Au compass shaped NPs can be self-assembled into two dimensional (2D) monolayer with closely packed and highly aligned
NPs, which results in periodic arrays of overlapped Au tips, generating hot spots for high-performance surface-enhanced Raman scattering (SERS).