表面增强能量转移效应的研究

通过分析2、2′菁染料水溶液、银胶体以及2、2′菁染料吸附于银胶表面时的吸收光谱得知,2、2′菁染料吸附于银胶表面时,有J聚集体出现,通过分析基频及高阶线性Raman光谱,证实了一些低波数的Raman信号是由J聚集体产生的,从而进一步证实了吸附于银胶表面的2、2′菁染料以单体和J聚集体形式共存.同时,由吸收光谱还可以看出,2、2′菁染料分子及其J聚集体分子的吸收带都处于银胶吸收带的半高宽范围内,满足共振条件,当用不同激发波长(514.5 nm和488 nm)的光激发吸附于银胶表面的2、2′菁染料时,观察到了J聚集体的敏化荧光,而用此激发光激发2、2′菁染料水溶液时,就没有观察到J聚集体的敏化荧光,从而说明了银胶表面的存在,加速了单体2、2′菁染料分子与其J聚集体分子之间的能量转移速率.

The Study of Surface Enhanced Energy Transfer Effect

On the basis of absorption spectra of 2,2′-cyanine solution,cilver colloid and 2,2′-cyanine adsorbed on cilver colloid, it was found that the J-aggregated molecule was formed when 2,2′-cyanine adsorbed on cilver colloid. By analyzing the fundamental and higher order linear Raman scattering of J-aggregated molecule adsorbed on cilver colloid, it was indicated that some of the low frequency bands in Raman spectrum are mainly due to J-aggregated molecule. This result proved that when 2,2′-cyanine adsorbed on cilver colloid, it co-exists in the form of monomer and J-aggregated molecule.On the other hand ,by using different wavelength (514.5 nm、488.0 nm) exciting 2,2′-cyanine adsorbed on cilver colloid, the fluorescence of J-aggregated molecule has been observed. However, the fluorescence of J-aggregated molecule hasn′t been detected in the solution of 2,2′-cyanine .This result illustrated that the existence of cilver colloid could accelerate the energy transfer rate between 2,2′-cyanine and its J-aggregated molecule.