多孔金纳米结构阵列的SERS效应检测痕量多氯联苯

Polychlorinated biphenyls (PCBs) are classified into the category of persistent organic pollutants, being harmful to environment and human health. Conventional detection methods for PCBs have low sensitivity and are generally complex, expensive, and time-consuming. Thus developing a simple, fast, economic, and sensitive method for trace detection of PCBs is exigent. Surface-enhanced Raman scattering (SERS) shows advantages of simplicity, rapidity and high sensitivity. However, the fabrication of highly sensitive and reproducible SERS substrates still remains a challenge. In this project, we will construct periodically arranged arrays of porous gold nanostructures inside the nanochannels of porous anodic aluminum oxide templates in a galvanic cell. Owning to the uniform morphologies of the porous gold nanostructure arrays, they will shows good reproducibility when used as SERS substrates for detecting PCBs. Meanwhile, to obtain SERS substrates with high sensitivity, we adjust the morphologies of the porous gold nanostructures and further reveal the relationship between their morphologies and the SERS performances. Finally, the porous gold nanostructure arrays are used as SERS substrates for simple, fast, and sensitive detection of trace PCBs. This project would facilitate the detection of PCBs in the real environment.

多氯联苯(PCBs)属持久性有机污染物，对环境和人类健康危害严重。传统的PCBs检测技术繁琐、灵敏度低、耗时长且成本高，因此，开发简便、廉价、快速、高精度的PCBs检测技术迫在眉睫。表面增强拉曼散射(SERS)技术具有简单、快捷、灵敏度高等优点，但同时存在两个关键难题：一是如何保证SERS信号的重复性；二是如何提高SERS基底的活性。本项目拟基于原电池原理在多孔阳极氧化铝模板中制备形貌和结构均一、有序的多孔金纳米结构阵列，采用该有序纳米结构阵列作为SERS基底，可以有效解决PCBs检测中SERS信号的重复性难题；同时，调控该SERS基底的形貌和结构，揭示不同结构参数的SERS基底与其活性之间的关联规律，优化基底形貌和结构，进而提高其SERS活性；最后，利用该高活性SERS基底实现对痕量PCBs的快速、简便、高精度检测。该项目的实施将为PCBs的实际环境检测提供理论依据和技术保障。

多氯联苯(PCBs)是一种对环境和人类健康有着极大危害的持久性有机污染物。传统的PCBs检测技术过程繁琐、灵敏度低、耗时长且成本高，因此，开发简便、廉价、快速、高精度的PCBs检测技术至关重要。表面增强拉曼散射(SERS)技术具有简单、快捷、灵敏度高等优点，但存在如何保证SERS信号的重复性和提高基底活性这两个关键难题。为了解决这两个难题，本项目首先采用电化学沉积法在多孔阳极氧化铝模板里构筑了有序的多孔Au纳米棒阵列。研究结果表明，该纳米棒阵列作为SERS基底具有良好的信号重复性与较高的SERS活性。然而，该纳米棒阵列SERS基底对PCBs的敏感性较低。随后，我们通过在多孔Au纳米棒的内、外表面原位沉积一层很薄的Ag包覆层，构筑了高度有序的多孔Au@Ag(芯@壳)纳米棒阵列。该纳米棒阵列SERS基底不但具有较高的活性和良好的信号重复性，且对PCBs及其混合物具有较高的SERS敏感性。利用多孔Au@Ag纳米棒阵列的SERS效应，我们实现了对痕量PCBs的快速、简便、高精度探测，达到了本项目的预期目标。本项目的实施将为推动PCBs的实时环境检测奠定基础。