用近边X射线吸收精细结构谱(NEXAFS)和同步辐射电子能谱(SRPES)技术,研究了单壁碳纳米管(SWCNTs)吸附色氨酸(Trp)的机理。对比Trp吸附于SWCNTs前后样品C-K边NEXAFS谱,发现SWCNTs与吸附的Trp之间存在明显的界面相互作用。吸附前后N-K边NEXAFS谱的峰形和峰位的变化可忽略,这表明Trp中的两个N原子都未参与界面相互作用。吸附后O-K边NEXAFS谱的边前峰更尖更强,这表明C=O的O原子参与了界面相互作用;吸收主峰的峰形的明显变化,则C=O和C-O的O原子都有可能参与界面相互作用,而O1s SRPES谱证实仅有C=O中的O原子参与了界面相互作用。
Near edge X-ray absorption fine structure spectroscopy(NEXAFS) and synchrotron radiation photoelectron spectroscopy(SRPES) were employed to investigate the adsorption mechanism of tryptophan(Trp) onto single-walled carbon nanotubes(SWCNTs).The difference of the carbon K-edge NEXAFS spectra between Trp molecules and Trp-adsorbed SWCNTs shows that a significant interaction occurs among the SWCNTs and Trp molecules adsorbed.However,negligible changes in the peak profiles and energy positions of nitrogen K-edge imply that neither of the two nitrogen atoms in Trp molecule is involved in the interface interaction.A change of the shape of the main absorption peak at the oxygen K-edge reveals that O atoms of the C=O or C-O or both are likely involved in the interface interaction.The fact that the peak at about 529 eV at the O K-edge become sharper and stronger demonstrates that the O atom in the C=O participates in the interface interaction,which was confirmed by O1s SRPES spectrum.