Department of Chemistry, East Tehran Branch, Islamic Azad University, Tehran, Iran.
Department of Chemistry, North Tehran Branch, Islamic Azad University, Tehran, Iran.
J Mol Graph Model. 2018 May;81:168-174. doi: 10.1016/j.jmgm.2018.03.002. Epub 2018 Mar 13.
The effect of replacing an Si atom of a silicon nanocone (SiNC) by Al or P atom on its electronic and field emission properties was investigated using density functional theory calculations. Molecular electrostatic potential surface indicates that the electrons do not spread out on the surface of SiNC evenly, and they tend to accumulate more at the apex, facilitating the electron emission from this site. Replacing an Si atom of the apex of nanocone by Al and P atoms is energetically more favorable than that of the wall by about 12.0 and 8.8 kcal/mol, respectively. Both Al- and P-doping processes increase the SiNC electrical conductivity, but the electron emission from the surface of SiNC increases after the P-doping and decreases by Al- doping. The electron emission in the P-doped SiNC is predicted to be about 600 times greater than that of the pristine SiNC at room temperature. The Al- or P-doping makes the SiNC a p-type or n-type semiconductor.
使用密度泛函理论计算研究了用 Al 或 P 原子替代硅纳米锥（SiNC）中的 Si 原子对其电子和场发射性质的影响。分子静电势表面表明，电子在 SiNC 表面上不均匀地扩散，它们更倾向于在顶点处积累，从而促进了该位置的电子发射。用 Al 和 P 原子替代纳米锥顶点的 Si 原子在能量上分别比替代壁面的原子更有利，约为 12.0 和 8.8 kcal/mol。Al 和 P 掺杂过程均增加了 SiNC 的电导率，但掺杂后 SiNC 的表面电子发射增加，掺杂 Al 后则减少。预测在室温下，掺杂 P 的 SiNC 的电子发射大约比原始 SiNC 高 600 倍。Al 或 P 掺杂使 SiNC 成为 p 型或 n 型半导体。
