Department of Biochemistry, School of Medicine, College of Medicine, Taipei Medical University, No. 250, Wu-Hsing St, Taipei 11031, Taiwan.
Analyst. 2012 Dec 21;137(24):5906-12. doi: 10.1039/c2an35829h.
As is shown in the literature, surface-enhanced Raman scattering (SERS)-active Ag films obtained by the salting-out of Ag colloids from solutions with some salts, are popularly used to examine the structure of analytes. SERS-active Ag nanoparticles (NPs) demonstrate more significant SERS effects than Au NPs, however, problems regarding the stabilities of SERS-active Ag NPs remain to be overcome. In this work, Ag/Al(2)O(3) colloids were prepared in 0.1 M HNO(3) solutions containing Al(2)O(3) NPs with higher heat capacity by sonoelectrochemical methods. SERS-active Ag/Al(2)O(3) films deposited on glass slides were prepared by the addition of a saturated NaCl solution in the prepared Ag/Al(2)O(3) colloids-containing solution. In an acceptable sacrifice of Raman intensity by ca. 30% magnitude, the prepared Ag/Al(2)O(3) films markedly improved thermal stability by raising the operation temperature over 100 °C, compared to Ag films. Meanwhile, aging of SERS enhancement capability in an atmosphere of relative humidity (RH) of 50% and 20% (v/v) O(2) at 30 °C is significantly depressed using Ag/Al(2)O(3) films.
如文献所示，通过从含有某些盐的溶液中盐析 Ag 胶体来获得的表面增强拉曼散射 (SERS)-活性 Ag 薄膜，常用于研究分析物的结构。SERS-活性 Ag 纳米粒子 (NPs) 比 Au NPs 表现出更显著的 SERS 效应，然而，SERS-活性 Ag NPs 的稳定性问题仍有待解决。在这项工作中，通过超声电化学方法在含有 Al2O3 NPs 的 0.1 M HNO3 溶液中制备了 Ag/Al2O3 胶体，Al2O3 NPs 的热容更高。通过在制备的含 Ag/Al2O3 胶体的溶液中添加饱和 NaCl 溶液，在载玻片上制备了 SERS 活性 Ag/Al2O3 薄膜。与 Ag 薄膜相比，在牺牲约 30%的拉曼强度的情况下，通过将操作温度提高到 100°C 以上，制备的 Ag/Al2O3 薄膜显著提高了热稳定性。同时，使用 Ag/Al2O3 薄膜显著抑制了在相对湿度 (RH) 为 50%和 20%（v/v）O2 的气氛中在 30°C 下的 SERS 增强能力的老化。
