碳掺杂氮化硼纳米管吸附气体小分子的DFT计算

采用密度泛函理论研究了氮化硼纳米管(Boron nitride nanotubes,BNNTs)及碳掺杂氮化硼纳米管对O2、NO2、F2气体小分子的气敏特性。计算了三种气体小分子吸附在氮化硼纳米管及碳掺杂氮化硼纳米管表面不同位置时的吸附能、相互作用距离,同时还计算得到了气体分子分别吸附在碳掺杂BNNTs不同位置时的电子态密度。研究结果表明,氮化硼纳米管对O2、NO2、F2气体分子比较敏感,碳掺杂氮化硼纳米管可以明显地改变其表面的化学反应活性,增强气体分子与氮化硼纳米管之间的相互作用。

DFT calculations on the adsorption of small gas molecules onto C-doped boron nitride nanotubes

Background: Chemical sensors that work as electronic noses have attracted extensive attention, yet research about sensor application of C-doped boron nitride nanotubes is still rare.Purpose: In order to realize the gas sensing properties of boron nitride nanotubes (BNNTs) and C-doped BNNTs for some small gas molecules, such as NO2, O2 and F2, we calculated the adsorption property of those gas molecules.Methods: The gas sensing properties of C-doped BNNTs for some small gas molecules have been investigated by using the density functional theory. Results: The interaction distance between gas molecule and BNNT and adsorption energy of gas molecule on the BNNTs and the C-doped BNNTs are obtained by density functional theory (DFT) calculation. We also calculated the electron densities of states for an O2 molecule or a NO2 molecule or a F2 molecule to adsorb on the different positions of C-doped BNNTs.Conclusion: The calculated results show that BNNTs present high sensitivity to the gaseous NO2, O2 and F2molecules. The chemical reactivity of BNNTs has been changed by carbon molecules, and C-doped BNNTs can improve the interaction between the gas molecules and the BNNTs.