水分散多壁碳纳米管紫外光谱特征及其应用

Characteristics of ultraviolet spectrum of multi-walled carbon Nanotubes in water dispersion system and Its application

研究了多壁碳纳米管水分散体系的紫外光谱特征及其影响因素,并将其应用于碳纳米管对环境污染物五氯苯酚的吸附过程。结果表明：水分散多壁碳纳米管的主吸收带在190~250nm;最大吸收峰位于190~207nm,且随碳纳米管管外径的增加向短波方向偏移;抽滤次数n影响水分散体系中碳纳米管的浓度及其紫外光谱强度,n≥4时吸收强度趋于稳定低值。紫外光谱法研究碳纳米管吸附五氯苯酚的体系中,选用232nm作为测定波长可得到良好的线性关系且避免碳纳米管背景浓度的干扰。

Characteristics of ultraviolet spectrum of multi-walled carbon nanotubes（MWCNTs）in water dispersion system and the influencing factors such as diameters of MWCNTs were investigated.The results showed that the major UV absorption band of MWCNTs was in 190-250nm.The maximum absorption peak was at 207nm for MWCNTs（diameter 8nm）and the blue shifts occured with the increasing diameter of MWCNTs.The frequency of decompress filtration influenced the concentration of MWCNTs and then the intensity of UV absorption in the water dispersion system.The results can be applied to a ultra-violet spectroscopic study of adsorption of pentachlorophenol on MWCNTs.If the UV wavelength at 232nm insteaded of 217nm was chose as a measuring value,the interference by the background absorption of MWCNTs can be minimized in this mixing system.