TiCl_(4)分子填充扶手椅型碳管的条件控制及光电性能理论研究

Theoretical Studies on Condition Control and Photoelectric Properties of Armchair Carbon Nanotubes Filled with TiCl_(4)Molecular

采用第一性原理与蒙特卡罗方法研究TiCl_(4)气体分子填充扶手椅型碳纳米管的吸附性能与光电性质,结果表明:扶手椅型碳纳米管对TiCl_(4)气体分子具有较强的物理吸附作用,研究构型的吸附能绝对值均超过0.9 eV,是TiCl_(4)气体分子理想的填充载体,随碳纳米管管径的增大,吸附能先增大后减小;温度升高不利于TiCl_(4)气体分子吸附,气体逸度增加有利于吸附,TiCl_(4)气体分子填充扶手椅型碳纳米管宜将温度维持在TiCl_(4)沸点附近,并增加气体的压力;TiCl_(4)的吸附对碳纳米管的电子结构进行了调控,使费米能级附近的态密度显著提高,使复合物的导电性增强,对赝能隙的大小没有明显影响,峰位仍由碳纳米管自身决定;TiCl_(4)的吸附对体系的光学参数影响有限,在增强复合物导电性的同时未使可见光区域吸收率、反射率、损失函数数值增大,可有效提升透明导电薄膜的性能。

First-principles calculations and Monte Carlo methods were carried out to study the adsorption properties and photoelectric properties of TiCl_(4)gas molecules in armchair carbon nanotubes.The results reveal that:armchair carbon nanotubes have a strong physical adsorption effect on TiCl_(4)gas molecules.The absolute values of the adsorption energy of the studied configurations are more than 0.9 eV,which makes armchair carbon nanotubes ideal filling carriers for TiCl_(4)gas molecules.As the diameter of carbon nanotubes increases,the adsorption energy first increases and then decreases.The increase of temperature is not conducive to the adsorption of TiCl_(4)gas molecules,and the increase of gas fugacity is conducive to the adsorption.The temperature should be maintained near the boiling point of TiCl_(4)and the pressure of the gas increases when TiCl_(4)gas molecules are inserted into armchair carbon nanotubes.The adsorption of TiCl_(4)regulates the electronic structure of carbon nanotubes,significantly improves the density of states near the Fermi level,enhances the conductivity of the composite,has no significant effect on the size of the pseudo-energy gap,and the peak position is still determined by the carbon nanotubes themselves.The adsorption of TiCl_(4)has a limited effect on the optical parameters of the system.While enhancing the conductivity of the composite,it does not increase the absorbance,reflectivity and loss function values in the visible region,which can effectively improve the performance of transparent conductive films.