High quality gold nanorods and nanospheres for surface-enhanced Raman scattering detection of 2,4-dichlorophenoxyacetic acid
High quality gold nanorods and nanospheres for surface-enhanced Raman scattering detection of 2,4-dichlorophenoxyacetic acid
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用于 2,4-二氯苯氧基乙酸表面增强拉曼散射检测的高质量金纳米棒和纳米球
DOI：
10.1088/0957-4484/23/49/495710
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发表时间：
2012-12-14
期刊：
影响因子：
3.5
通讯作者：
Xu, Bo-Qing
中科院分区：
文献类型：
--
作者：
Jia, Jin-Liang;Xu, Han-Hong;Xu, Bo-Qing
使用梯度离心方法从家庭合成的多分散样品中分离出具有不同纵横比的近单分散金纳米棒（NR）。通过透射电子显微镜、原子力显微镜和紫外可见光谱分析了其形貌、尺寸及其分布以及光吸收性能。随后，使用离心后产率 97.4% 的胶体 Au NR（36.2 nm x 10.7 nm）和产率 97.6% 的金纳米球（NSs）（直径 22.9 +/- 1.0 nm）作为 Au 底物，使用激光激发在632.8 纳米。结果表明，使用 1.0 x 10(-6) M 2,4-D 时，Au NRs 和 NSs 的表面增强因子 (EF) 分别为 6 .2 x 10(5) 和 5.7 x 10(4)，说明 Au NRs 基底的 EF 值比 Au NSs 基底大 10 倍左右。因此，大的 EF 主要是化学增强机制的结果。因此，金纳米粒子有望在农药残留痕量检测中得到全面的SERS应用。
Nearly monodisperse Au nanorods (NRs) with different aspect ratios were separated from home-synthesized polydisperse samples using a gradient centrifugation method. The morphology, size and its distribution, and photo-absorption property were analyzed by transmission electron microscopy, atomic force microscopy and UV-visible spectroscopy. Subsequently, using colloidal Au NRs (36.2 nm x 10.7 nm) with 97.4% yield after centrifugation and Au nanospheres (NSs) (22.9 +/- 1.0 nm in diameter) with 97.6% yield as Au substrates, surface-enhanced Raman scattering (SERS) spectra of 2,4-dichlorophenoxyacetic acid (2,4-D) were recorded using laser excitation at 632.8 nm. Results show that surface enhancement factors (EF) for Au NRs and NSs are 6 .2 x 10(5) and 5.7 x 10(4) using 1.0 x 10(-6) M 2,4-D, respectively, illustrating that EF value is a factor of similar to 10 greater for Au NRs substrates than for Au NSs substrates. As a result, large EF are a mainly result of chemical enhancement mechanisms. Thus, it is expected that Au NPs can find a comprehensive SERS application in the trace detection of pesticide residues.