High-Yield Synthesis of Hollow Octahedral Silver Nanocages with Controllable Pack Density and Their High-Performance Sers Application
High-Yield Synthesis of Hollow Octahedral Silver Nanocages with Controllable Pack Density and Their High-Performance Sers Application
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可控堆积密度的空心八面体银纳米笼的高产合成及其高性能系列应用
DOI：
10.1002/smll.201602280
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发表时间：
2016-10-19
期刊：
影响因子：
13.3
通讯作者：
Guo, Lin
中科院分区：
文献类型：
--
作者：
Huang, Fengqin;Ma, Guanshui;Guo, Lin
采用基于cu20的模板辅助策略，成功地合成了具有锋利边缘的纳米粒子组装银纳米笼。在该反应体系中，Ag纳米粒子可以在Cu2O八面体表面自组装，这是在柠檬酸钠作为封盖剂存在的情况下，通过NaBH4还原Ag+来实现的。用乙酸除去内部的Cu2O芯，得到中空的八面体银纳米笼。扫描电镜（SEM）和透射电镜（tem）表征表明，银纳米笼由细小的纳米颗粒编织而成，粗糙的表面布满孔洞和锋利的边缘。结果表明，银纳米粒子的堆积密度对表面增强拉曼散射（SERS）活性有较大影响。包覆密度最佳的1.05-Ag网箱具有合适的颗粒间距和孔径，显著增强了SERS信号。罗丹明6G （R6G）分子在10(-14)M的超低浓度下，以1.05-Ag笼为底物，可以检测到SERS信号。除了灵敏度外，1.05-Ag笼还具有良好的再现性。超高的灵敏度使银纳米笼有望成为基于sers的高性能化学传感器。
Nanoparticle-assembled octahedral Ag nanocages with sharp edges have been successfully synthesized through a Cu2O-based template-assisted strategy. In the reaction system, Ag nanoparticles can be self-assembled on the surface of Cu2O octahedrons, which is accomplished by the reduction of Ag+ by NaBH4 in the presence of sodium citrate as a capping agent. The hollow octahedral Ag nanocages are obtained after removing the inner Cu2O cores with acetic acid. According to the scanning electron microscopy (SEM) and transmission electron microscopy characterization, the Ag nanocages are weaved by small nanoparticles, the rough surfaces are bestrewed with pores and sharp edges. It is found that the pack density of Ag nanoparticles strongly affects the surface enhanced Raman scattering (SERS) activities. The as-prepared 1.05-Ag cages with optimal pack density have suitable interparticle distance and suitable size of pores, which significantly enhance SERS signals. The SERS signals of rhodamine 6G (R6G) molecules can be detected at an ultralow concentration of 10(-14) M when 1.05-Ag cages are used as substrates. In addition to sensitivity, 1.05-Ag cages also exhibit good reproducibility. It is expected that the ultrahigh sensitivity will endow the Ag nanocages to become a promising candidate as high-performance SERS-based chemical sensor.