Xue Bin, Wang Dan, Zuo Jing, Kong Xianggui, Zhang Youlin, Liu Xiaomin, Tu Langping, Chang Yulei, Li Cuixia, Wu Fei, Zeng Qinghui, Zhao Haifeng, Zhao Huiying, Zhang Hong
State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China.
Nanoscale. 2015 May 7;7(17):8048-57. doi: 10.1039/c4nr06901c.
The great application potential of triangular silver nanoprisms (TSNPRs, also referred to as triangular silver nanoplates) is hampered by the lack of methods to produce well-defined tips with high monodispersity, with easily removable ligands. In this work, a simple one-step plasmon-mediated method was developed to prepare monodisperse high-quality TSNPRs. In this approach, the sole surface capping agent was the easily removable trisodium citrate. Differing from common strategies using complex polymers, OH(-) ions were used to improve the monodispersity of silver seeds, as well as to control the growth process through inhibiting the oxidation of silver nanoparticles. Using these monodisperse high-quality TSNPRs as building blocks, self-assembled TSNPRs consisting of six-tip based "hot spots" were realized for the first time as demonstrated in a high enhancement (∼10(7)) of surface-enhanced Raman scattering (SERS). From the plasmon band shift versus the refractive index, ultra-high local surface plasmon resonance sensitivity (413 nm RIU(-1) or 1.24 eV RIU(-1), figure of merit (FOM) = 4.59) was reached at ∼630 nm, making these materials promising for chemical/biological sensing applications.
三角形银纳米棱柱（TSNPRs，也称为三角形银纳米片）具有巨大的应用潜力，但由于缺乏制备具有高单分散性且配体易于去除的明确定义尖端的方法而受到阻碍。在这项工作中，开发了一种简单的单步等离子体介导方法来制备单分散的高质量TSNPRs。在这种方法中，唯一的表面封端剂是易于去除的柠檬酸钠。与使用复杂聚合物的常见策略不同，OH(-)离子用于提高银种子的单分散性，并通过抑制银纳米颗粒的氧化来控制生长过程。首次使用这些单分散的高质量TSNPRs作为构建块，实现了由基于六个尖端的“热点”组成的自组装TSNPRs，如表面增强拉曼散射（SERS）的高增强（10(7)）所示。从等离子体带移与折射率的关系来看，在630nm处达到了超高的局部表面等离子体共振灵敏度（413nm RIU(-1)或1.24eV RIU(-1)，品质因数（FOM）=4.59），这使得这些材料在化学/生物传感应用中很有前景。
