亚甲基蓝的催化降解和原位 SERS 监测

文章采用表面增强拉曼散射(surface-enhanced Raman scattering, SERS)技术对亚甲基蓝的降解反应过程进行原位实时监测。以银纳米线和苯乙烯-乙烯-丁烯-苯乙烯(SEBS)嵌段共聚物为材料，通过界面组装方法成功制备了高效、通用的SERS基底。该基底具有超疏水作用，接触角达到121.3°，保证了亚甲基蓝降解过程的原位实时监测；该基底具有超高的SERS响应，实验证明，基底对亚甲基蓝的检出限低至 $ 10^{-13} $ mol/L；具有良好的信号重现性，相对标准偏差(relative standard deviation, RSD)为9.26%。此外，作为一种实用的SERS基底，能够催化硼氢化钠对亚甲基蓝的降解，结果表明，SERS基底具有良好的催化效果，在150 s内亚甲基蓝的降解率高达99.90%。

In this paper, surface-enhanced Raman scattering (SERS) technique was used to monitor the degradation process of methylene blue in situ and in real time. Using silver nanowires and styrene-ethylene-butene-styrene (SEBS) block copolymer as materials, an efficient and universal SERS substrate was successfully prepared by interface assembly method. The substrate has a superhydrophobic effect and the contact angle reaches $ 121.3^{\circ} $, which ensures the in situ real-time monitoring of methylene blue degradation process. Meanwhile, the SERS response is extremely high. Experiments prove that the detection limit of methylene blue is as low as $ 10^{-13} $ mol/L. The substrate also has good signal reproducibility, with a relative standard deviation (RSD) of 9.26%. In addition, as a practical SERS substrate, it can catalyze the degradation of methylene blue by sodium borohydride. The results show that the SERS substrate has a good catalytic effect, and the degradation rate of methylene blue is up to 99.90% in 150 s.