通过第一性原理密度泛函理论的方法,研究了Stone-Wales缺陷和C掺杂对手性BN纳米带的带隙调控。结果表明,Stone-Wales缺陷使得BN纳米带的价带顶(VBM)和导带底(CBM)的占据态发生变化,从而引入了缺陷能级降低了带隙,但Stone-Wales缺陷的个数对带隙的大小影响不明显。电子结构计算表明,带Stone-Wales缺陷的BN纳米带的缺陷能级主要是由VBM附近形成N-N原子的类π键轨道和CBM附近形成B-B原子的类σ键分布决定。通过在带Stone-Wales缺陷的BN纳米带中引入C掺杂改变杂质能级的分布,在VBM附近形成了C-C原子的类σ键轨道和CBM附近形成了C-B原子的类σ键,这样可以进一步降低BN纳米带的带隙,拓展了BN纳米带的应用。
Based on density functional theory,the band gap modulation of chiral BN nanoribbon by Stone-Wales defects and C doping was studied in this paper. The calculated results show that the Valence Band Maximum( VBM) and Conduction Band Minimum( CBM) of BN nanoribbon could be changed by appearance of Stone-Wales defects and the band gap decreases since the defect energy level is introduced,while the number of the Stone-Wales defects has little influence on band gap width. The electronic structure calculations show that the defect energy level of BN nanoribbon with Stone-Wales defect are decided by the N-N atoms π orbital nearby VBM and the B-B atoms σ bond nearby CBM. The impurity energy levels can be further introduced in the BN nanoribbon with Stone-Wales defect by C doping,which generated by C-C atoms σ bond nearby VBM and C-B atoms σ bond nearby CBM to reduce the band gap of BN nanoribbon and expand its application.