羟基化碳纳米管检测油中溶解气体的理论分析

Theoretical Analysis on Hydroxylation Carbon Nanotubes Detecting Gases in Oil

为检测油中溶解气体,应用密度泛函理论,通过计算机量子力学模拟研究了羟基侧壁修饰的(8,0)单壁碳纳米管(SWNT-OH)对变压器油中溶解气体分子C2H2、CH4、C2H4、CO、H2的吸附特性。计算得到的吸附能、净电荷转移量、作用距离及电子态密度表明,SWNT-OH对油中溶解气体分子的吸附属于物理吸附,且吸附气体分子之后,SWNT-OH的几何结构和电子结构都发生了变化。SWNT-OH对有机分子(C2H2、CH4、C2H4)的吸附能力大于对无机分子(CO、H2)的吸附能力,在有机分子中对C2H2的吸附能力最大。因此,预测SWNT-OH可以作为检测变压器油中溶解的C2H2气体的新型气体传感器。

Characteristics of hydroxyl side wall modification （8,0） single wailed carbon nanotubes （SWNT-OH） absorbing C2H2, CH4, C2H4, CO and H2 in transformer oil were investigated using the density functional theory through quantum mechanics simulation by computer. The calculated results including binding energies, net charge transfer, interacting distance and electronic density of states show that the adsorption between SWNT-OH and gas molecules in oil is physical adsorption. Besides, geometric structures and electronic properties of SWNT-OH will change after absorbing the gas molecules. The adsorption capacity of organic gas molecules is larger than that of inorganic gas molecules, and among organic gas molecules, the adsorption capacity of C2H2 is the largest, so it is predicted that SWNT-OH can serve as new gas sensors to detect C2H2 in transformer oil.