羧基修饰石墨烯吸附SF6分解组分的DFT计算

DFT Study on Adsorption of SF6 Decomposition Components by Hydroxyl and Carboxyl Groups Modified Graphene

为研制高灵敏度SF6气体分解组分检测传感器,利用基于第一性原理的密度泛函理论(DFT)方法,采用分子模拟软件对SF6主要放电分解组分(SO2,SOF2,SO2F2,CF4)在羧基修饰石墨烯表面的吸附特性进行了模拟计算,从微观角度研究了羧基修饰石墨烯检测SF6气体放电分解组分的气敏机理。理论计算了单分子吸附过程中表征吸附性能特征参量的吸附能、吸附距离、净电荷转移量、分子前线轨道以及态密度。结果表明:羧基的修饰能够有效提高石墨烯的吸附性能,且羧基石墨烯效果更好,对4种分子吸附效果强弱依次为SO2>SOF2>SO2F2>CF4,其中SO2在羧基石墨表面发生较为强烈的化学吸附效应。

In order to develop a high sensitivity SF6 gas decomposition component detection sensor,the adsorption characteristics of main discharge decomposition components(SO2,SOF2,SO2 F2,CF4)of SF6 on carboxyl modified graphene surface were simulated by using density functional theory based on first principles and molecular simulation software.The adsorption energies,adsorption distances,net charge transfer,Molecular Frontier orbits and density of states of the characteristic parameters characterizing the adsorption properties were calculated theoretically.The results show that carboxyl modification can effectively improve the adsorption performance of graphene,and carboxyl graphene has a better adsorption effect.The order of the four molecules is SO2>SOF2>SO2 F2>CF4.SO2 has a strong chemical adsorption effect on the surface of carboxyl graphite.