Pd OECC薄膜的表面增强拉曼散射

Surface Enhanced Raman Scattering of Pd OECC Thin Film

利用较高检测灵敏度的 SERS技术 ,对浓度较低的 Pd OECC吸附在银表面上的薄层在室温下进行了拉曼谱的测量。得到 Pd OECC在强光破坏前后的 SERS光谱。在强光照射下 ,β-胡萝卜素分子的 SERS光谱的散射强度明显降低 ,且线宽增加 ,说明强光照射不但改变了β-胡萝卜素的构象 ,而且也改变了 β-胡萝卜素分子所处的微环境。其结果与强光照射前后吸收光谱的变化相一致。另外 ,没有观察到 Pd OECC薄层与银镜相互作用的其它新振动峰或Pd OECC中其它振动峰峰型的变化 ,可见 Pd OECC在银镜表面保持原来的状态 。

We have measured the Surface Enhanced Raman scattering (SERS) spectrum of a thin film of Pd OECC (Purified Oxygen Evolution Core Complexes) on a silver mirror at room temperature. Relative to the SERS of normal Pd OCEE, the SERS of thin film Pd OECC after strong illumination shows a decrease in scattering intensity and an increase in linewidths of the bands. These indicate a change in the conformation and microenvironment of the β carotene pigment. The SERS results are consistent with the changes seen in the absorption spectrum of Pd OECC induced by strong illumination. In contrast, there is no change that can be ascribed of new vibrational bands. It is deduced that Pd OECC on the silver mirror is identical to that in solution. In summary, SERS proves to be a good method to study the photo damage mechanism in photosynthesis.