Investigation on the Selective Separation of Chiral Carbon Nanotubes by Photoselective Laser Excitation at the Wave length of the Resonance Absorption Bands

本报告由两部分组成。第一部分研究了选择性激光照射下碳纳米管在增溶溶液中光选择性分离的必然性。。B部分是使用洗涤剂和生物聚合物增溶的单壁碳纳米管溶液的物理化学。。用高功率光参量振荡器脉冲激光在手性结构的共振吸收带激发，研究了分散在洗涤剂或生物聚合物溶液中的单壁碳纳米管对金属碳纳米管和半导体单壁碳纳米管(m-SWNT和S-SWNT)的手性选择性分离。在激发波长为M_(11)、(507 Nm)、S_(22)和S_(Lt)；11&gt；(977 Nm)。M&lt；11&gt；的最高键能降解了Carb…的结构脉搏数越多，管腔越完整。而S带和S带的激发只对S-单壁碳纳米管有损伤作用，而对m-碳管的结构没有影响。结果表明，单壁碳纳米管溶液在S-单壁碳纳米管的波长范围内的发射能以牺牲S-单壁碳纳米管为代价得到m-单壁碳纳米管的浓集。拉曼光谱和原子力显微镜测量表明，在半导体波长的激发下发生了热化。为了获得更多的选择性手性激光分离增溶剂，研究了十二烷基硫酸钠(SDS)或羧甲基纤维素(CMC)等多种洗涤剂或生物聚合物对单壁碳纳米管在溶液中的增溶作用。结果表明，增溶的单壁碳纳米管在CMC溶液中的稳定性对溶液的温度变化非常敏感。随着温度的升高或下降，SWCNT在CMC中的增溶溶液是不可逆的。这表明，在CMC溶液中溶解的单壁碳纳米管有望成为一种良好的增强剂，因为在激光激发波长下，随着温度的升高，单壁碳纳米管与溶液中的单壁碳纳米管分离较少，有望成为一种良好的光选择性手性分离试剂

This report is consisted of two parts. Part A is the inevestigation of the photoselective separation of carbon nanotube in the solubilized solution at the selective laser irradiatio. . The part B is the physical chemistry of the solubilized SWCNT solution by using detergents and bioploymer. . The investigation of the chiral selective separations of carbon nanotubes of the metallic and the semiconducting single-walled carbon nanotubes (m-SWNT&s-SWNT) has been pursued by the photoselective excitaion of the dispersed SWNT in the detergent or the biopolymer in solution at the high power OPO (optical parametric oscillator) pulsed laser excitation at the resonance absorption band of chiral structures.When the laser excitation was made for the aqueous SWCNT solution solubilized with NaDDBS (Dodecylbenzenesulfonic acid sodium salt) at the excitation wave length of M_<11> (507nm), S_<22> (732nm), and S_<11> (977nm), respectively. The highest bnand energy of M_<11> degraded the structure of carb … More onnanotube completely as the pulse number increased. However, the excitations at the wave length of S_<22> and S_<11> bands damaged only s-SWCNT, but did not give the structural damage of m-carbonanotubes. It indicates that the ecitations for the soliubilized SWCNT solution at the wave lengths of s-SWCNTs could give the concentrated m-SWNT at the sacrifice of s-SWCNT. Raman spectroscopic and AFM measurements revealed that there is ocurred the thermalization at the excitation of the semiconducting wave length. In order to have more idial solubilizing agents for the photo-selective chiral laser separation, the physical chemistry of the solubilized SWCNT in solution was invetstigated by using many kinds of detergents or biopolymer such as sodiumdodecylsulphate (SDS) or carboxymethylcellulose (CMC). It is found that the stability of the solubilized SWCNT in CMC solution is very sensitive for the temperature changes in the solution. The solubilized solution of SWCNT in CMC is irreversible for the rising temperature or the falling temperature changes. It indicates that the solubilized SWCNT in CMC solution is expected as a good agent for the enhancement of the photoselective chiral separation of SWCNT in solution, because the temperture rise will give the separation of SDWCNT from the solution at the laser excitaion wave length Less