Au/Si基底上电沉积Pt纳米层的衰减全反射表面增强红外吸收光谱

以一氧化碳为探针分子，研究了在金/硅基底上合理电沉积形成的铂纳米薄层的衰减全反射表面增强红外吸收效应．与外反射红外吸收光谱测得的本体铂电极表面上一氧化碳最大吸收峰强相比，铂纳米薄层的红外吸收增强了约10倍；与文献上的有关薄膜的反常红外效应相比，其峰的强度相当，但方向上却无倒转或出现双极．可应用于诸如甲醇电催化氧化的吸附中间体的灵敏检测．铂纳米膜的红外吸收增强，可能与其本身表面等离子振荡的激发有关．

Attenuate-Total-Reflection Surface-enhanced Infrared Absorption Spectroscopy on Pt Nano-layers Electrodeposited on a Au/Si Substrate

Surface-enhanced infrared absorption spectra of CO have been obtained on Pt nano-layers properly electrodeposited onto a Au/Si substrate with the Kretschmann attenuate-total-reflection (ATR) configuration. The overall intensity in reflectance for the linearly adsorbed CO band is enhanced by a factor of around 10, compared to the corresponding theoretical maximum values for bulk metal surfaces with the external infrared reflection and absorption spectroscopy (IRAS). In comparison to the so-called abnormal infrared effects (AIREs) in the literature, the band intensity is comparable whereas the band direction is normal in the present study. Surface enhanced IR absorption effect of the above Pt nanolayer can be applied to characterize the intermediate species formed in methanol oxidation. The enhancement mechanism is briefly discussed based on surface plasmon oscillation excitable on the electrodeposited Pt surfaces.