【摘要】 在制备碳纳米管时经常出现气体吸附和原子掺杂等现象影响碳纳米管的场致发射性能,H2O分子和B原子就是重要的吸附物质。采用第一性原理深入探讨了掺B和吸附H2O对碳纳米管电子场致发射性能影响的物理机制。结果显示:与CNT+H2O比较,BCNT+H2O管顶局域态密度和费米能级处总态密度显著增加,体系的赝能隙减小,反映体系的金属性增强,势垒高度降低,因此掺B并吸附H2O提高了碳纳米管的场发射性能。更多还原

【Abstract】 Gas adsorption and atom doping usually occur in the process of preparing carbon nanotubes(CNT), and can affect its field emission properties. H2 O molecule and Boron atom are the important adsorbate respectively. Using ab-initio calculations, we have investigated the electron field emission performance of CNT simultaneously adsorbed with one H2 O molecule and doped with one Boron atom(BCNT + H2O) in this paper. The results indicate that the electrons localize at the top of BCNT +H2O and the electronic density of states(DOS) around the Fermi level enhance obviously, the pseudo gap increase, which reflects that the metal property of CNT enhances, and the barrier height reduces compared with CNT + H2 O. Therefore, B-doped and adsorbed H2 O can effectively improve the field-emission properties of carbon nanotubes.更多还原