Palladium-coated gold nanoparticles with a controlled shell thickness used as surface-enhanced Raman scattering substrate
Palladium-coated gold nanoparticles with a controlled shell thickness used as surface-enhanced Raman scattering substrate
复制标题
具有受控壳厚度的钯包金纳米颗粒用作表面增强拉曼散射基底
DOI：
10.1021/jp0652906
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发表时间：
2007-01-25
影响因子：
3.7
通讯作者：
Tian, Zhong-Qun
中科院分区：
文献类型：
--
作者：
Hu, Jia-Wen;Li, Jian-Feng;Tian, Zhong-Qun
我们报道了具有厚度受控外壳的金核钯壳（Au@Pd）纳米颗粒的合成和表征，作为表面增强拉曼散射（SERS）的改进过渡金属基底。通过改变H_2PdCl_4与Au的摩尔比，可以精确地控制Pd壳层的厚度，从几个纳米到大约100个纳米。一个单层利用透射电子显微镜（TEM），UV-vis，SERS和电化学技术进行了一系列表征。结果证实了核-壳结构以及Pd壳的均匀和无针孔的性质，确保了Pd的性质而不受Au的可能干扰。与理论预测一致，核-壳设置除了从Pd壳本身的增强之外，还通过长程电磁增强从Au核借用高SERS活性。此外，可以通过可调的壳层厚度和核尺寸来优化它们的SERS活性。nm-Au@Pd/Pd电极使我们能够在Pd上获得各种分子的高质量SER光谱，这在过去是无法获得细节的。我们相信，这种借款策略将是重要的，在原位提取详细的振动信息的吸附在催化Pd表面。
We report the synthesis and characterization of gold core palladium shell (Au@Pd) nanoparticles with thickness-controlled shell as an improved transition-metal substrate for surface-enhanced Raman scattering (SERS). By changing the molar ratio of H2PdCl4 to Au, the Pd shell thickness can be precisely controlled from a few nanometers down to ca. one monolayer. A series of characterizations were performed using transmission electron microscopy (TEM), UV-vis, SERS, and electrochemical techniques. The results confirmed the core-shell structure and the uniform and pinhole-free nature of the Pd shell, ensuring the properties of Pd without possible interference from Au. Consistent with theoretical prediction, the core-shell setting borrows high SERS activity from the Au core through the long-range electromagnetic enhancement in addition to the enhancement from the Pd shell itself. Moreover, their SERS activity can be optimized by the tunable shell thickness and core size. The nm-Au@Pd/Pd electrodes allow us to obtain good quality SER spectra of various molecules on Pd that were unable to be accessed with detail in the past. We believe that this borrowing strategy will be important for in-situ extracting of detailed vibrational information for adsorbates on catalytic Pd surfaces.