Silver Nanoparticles Coated Zinc Oxide Nanorods Array as Superhydrophobic Substrate for the Amplified SERS Effect
Silver Nanoparticles Coated Zinc Oxide Nanorods Array as Superhydrophobic Substrate for the Amplified SERS Effect
复制标题
DOI：
10.1021/jp201897j
复制
发表时间：
2011-05-26
影响因子：
3.7
通讯作者：
Li, Zhuang
中科院分区：
文献类型：
--
作者：
Xu, Fugang;Zhang, Yue;Li, Zhuang
探索了一种结合超疏水凝聚效应和银纳米氧化锌纳米棒阵列的高增强能力的超疏水衬底，用于表面增强拉曼散射(SERS)。首次研究了水接触角和液滴体积对最终SERS信号强度的影响。我们的结果表明，由于超疏水凝聚效应，超疏水衬底可以比普通亲水的银@氧化锌衬底表现出3倍的信号增强。这种信号放大效应受水滴在衬底上的接触角和水滴体积的影响，即(1)接触角越大，SERS信号越强；(2)SERS强度随水滴体积的增加而波动，应选择合适的体积，而不是最大的体积以获得更强的信号。最重要的是，这种具有高信号重复性的超疏水底物被成功地应用于腺嘌呤和三聚氰胺等小分子的检测，其检测下限比亲水的Ag@ZnO底物低1个数量级。这种超疏水SEA底物有望在未来的痕量分析中得到广泛的应用。
A superhydrophobic substrate that combines the superhydrophobic condensation effect and high enhancement ability of silver nanoparticle coated zinc oxide nanorods array (Ag@ZnO) is explored for surface enhanced Raman scattering (SERS). The effects of water contact angle and droplet volume on the final SERS signal intensity are also investigated for the first time. Our results indicate the superhydrophobic substrate could exhibit 3-fold signal enhancement more than the ordinary hydrophilic Ag@ZnO substrate due to the superhydrophobic condensation effect. This signal amplification effect is affected by the water contact angle and water droplet volume on the substrate, i.e., (1) the higher the contact angle is, the higher the SERS signal is; (2) the SERS intensity fluctuates as the droplet volume increases, and proper volume, not the largest one, should be chosen to achieve a stronger signal. Most importantly, this superhydrophobic substrate with high signal reproducibility is successfully applied to detect small molecules such as adenine and melamine, with the detection limits of 1 order of magnitude less than those on the hydrophilic Ag@ZnO substrate. It is expected this superhydrophobic SEAS substrate can be widely used in the trace analysis in the future.