Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanostructures, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei, 230031, China.
Nanoscale. 2014 May 7;6(9):4781-8. doi: 10.1039/c3nr06483b.
We report on a synthetic approach to produce self-supported flexible surface-enhanced Raman scattering (SERS) active membranes consisting of polyamide (PA) nanofibers grafted with vertical Ag-nanosheets, via a combinatorial process of electrospinning PA-nanofiber membranes, assembling Au-nanoparticles on the PA-nanofibers as seeds for subsequent growth of Ag-nanosheets, and electrodepositing Ag-nanosheets on the electrospun PA-nanofibers. As a high density of Ag-nanosheets are vertically grown around each PA-nanofiber in the three-dimensional (3D) networked PA-nanofiber membranes, homogeneous nano-scaled gaps between the neighboring Ag-nanosheets are formed, leading to a high density of 3D SERS "hot spots" within the Ag-nanosheet-grafted PA-nanofiber membranes. The Ag-nanosheet-grafted PA-nanofiber membranes demonstrate high SERS activity with excellent Raman signal reproducibility for rhodamine 6G over the whole membrane. For a SERS-based trial analysis of polychlorinated biphenyls (PCBs, a kind of global environmental hazard), the 3D SERS substrate membranes are modified with mono-6-β-cychlodextrin to effectively capture PCB molecules. As a result, not only a low concentration down to 10(-6) M is reached, but also two congeners of PCBs in their mixed solution are identified, showing promising potential in SERS-based rapid detection of trace organic pollutants such as PCBs in the environment.
我们报告了一种合成方法，通过电纺聚酰胺（PA）纳米纤维膜、在 PA 纳米纤维上组装金纳米粒子作为随后生长 Ag 纳米片的种子，以及在电纺 PA 纳米纤维上电沉积 Ag 纳米片，来制备由垂直 Ag 纳米片接枝的聚酰胺（PA）纳米纤维支撑的柔性表面增强拉曼散射（SERS）活性膜。由于在三维（3D）网络状 PA 纳米纤维膜中，每根 PA 纳米纤维周围垂直生长了高密度的 Ag 纳米片，因此在相邻的 Ag 纳米片之间形成了均匀的纳米级间隙，从而在 Ag 纳米片接枝的 PA 纳米纤维膜中形成了高密度的 3D SERS“热点”。Ag 纳米片接枝的 PA 纳米纤维膜对罗丹明 6G 表现出高 SERS 活性和优异的拉曼信号重现性，整个膜都如此。对于基于 SERS 的多氯联苯（PCBs，一种全球性环境危害物）试验分析，3D SERS 基底膜用单 6-β-环糊精进行修饰，以有效捕获 PCB 分子。结果不仅达到了低至 10(-6) M 的浓度，而且还能识别出混合溶液中的两种 PCB 同系物，这在基于 SERS 的快速检测环境中的痕量有机污染物（如 PCB）方面显示出了有前景的潜力。
