卤离子吸附竞争对罗丹明B-金胶体系NIR-SERS的影响

Effects of the Halide Ion Adsorption Competition on the Near-Infrared-Surface-Enhanced Raman Spectroscopy of Rhodamine B-Au Colloid Systems

在金纳米胶体体系中采用近红外激光(1064nm)激发,研究了卤素离子(Cl-、Br-、I-)对激光染料 罗丹明B(RhB)分子近红外表面增强拉曼散射光谱(NIR SERS)的影响,给出了表面增强拉曼谱随卤素离子加入顺序的不同的变化过程。结果表明,在此体系中卤素离子与分子共吸附能力的强弱顺序为Cl- Br-<I-;在三者共存情况下,也以I-优先吸附。同时利用紫外 可见吸收光谱间接证明了这一结论。

The interaction of Rhodamine B(RhB) and gold colloid surface was studied by surfaceenhanced Raman spectroscopy(SERS) with nearinfrared(NIR) excitation in the presence of the halide ions(Cl-,Br-,I-).The result showed that the interaction strength of halide ions with gold surface increases in the order of Cl-Br-<I-.Under the condition that these three kinds of halide ions coexist,I- ions will be adsorbed with the gold surface in priority.This conclusion is also been proved indirectly by the corresponding UVvisible spectroscopy of the system above.