卤素掺杂对多壁碳纳米管导电性能的影响

Influence of electrical conductivity of multi-walled carbon nanotubes by halogen-doping

通过气体吸附,制备了掺氯、溴、碘的多壁碳纳米管材料.与未掺杂多壁碳纳米管(MWNTs)相比,掺氯MWNTs电导率提高到原来的5倍以上,掺溴MWNTs电导率提高到原来的3倍左右,掺碘对MWNTs电导率基本无影响.用拉曼光谱和X光电子能谱(XPS)分析研究了卤素和MWNTs间的相互作用.同时研究了载流子浓度和迁移率对复合材料电导率的影响,结果表明:卤素的电负性越强,掺杂后多壁碳纳米管的载流子平均自由程提高越多,载流子迁移率提高越大;卤素与MWNT s之间的相互作用越强,产生的载流子越多,掺杂后的MWNTs载流子浓度提高越大.

Multi-walled carbon nanotubes （MWNTs） were doped by chlorine,bromine and iodine.Compared with the pristine MWNTs,the electrical conductivities of C12-MWNT and Br2MWNTs were improved over 5 times and 3 times,respectively,while that of I2-MWNTs almost unchanged.The interaction between the halogen and MWNTs was analyzed by Raman spectroscopy and X-ray photoelectron spectroscopy （XPS）.Meanwhile,we also studied the carrier concentration and carrier mobility which may affect the conductivities of the composite.The results show that：When the halogen electronegativity become stronger,the mean free path of the carrier of doped MWNTs will be higher,as well as the carrier mobility.And the stonger the interaction between the halogen and MWNTs become,the more carriers will take part in conducting,which means the carrier concentration will be higher.