Wu Bi-Ru, Yang Chih-Kai
Department of Natural science, Center for General Education, Chang Gung University, Kueishan 333, Taiwan, ROC.
Graduate Institute of Applied Physics, National Chengchi University, Taipei 11605, Taiwan, ROC.
Sci Rep. 2015 Oct 15;5:15310. doi: 10.1038/srep15310.
Hydrogen vacancies in graphane are products of incomplete hydrogenation of graphene. The missing H atoms can alter the electronic structure of graphane and therefore tune the electronic, magnetic, and optical properties of the composite. We systematically studied a variety of well-separated clusters of hydrogen vacancies in graphane, including the geometrical shapes of triangles, parallelograms, hexagons, and rectangles, by first-principles density functional calculation. The results indicate that energy levels caused by the missing H are generated in the broad band gap of pure graphane. All triangular clusters of H vacancies are magnetic, the larger the triangle the higher the magnetic moment. The defect levels introduced by the missing H in triangular and parallelogram clusters are spin-polarized and can find application in optical transition. Parallelograms and open-ended rectangles are antiferromagnetic and can be used for nanoscale registration of digital information.
石墨烷中的氢空位是石墨烯不完全氢化的产物。缺失的氢原子会改变石墨烷的电子结构，从而调节复合材料的电学、磁学和光学性质。我们通过第一性原理密度泛函计算系统地研究了石墨烷中各种间隔良好的氢空位团簇，包括三角形、平行四边形、六边形和矩形的几何形状。结果表明，缺失的氢在纯石墨烷的宽带隙中产生了能级。所有氢空位的三角形团簇都是磁性的，三角形越大，磁矩越高。三角形和平行四边形团簇中缺失的氢引入的缺陷能级是自旋极化的，可应用于光学跃迁。平行四边形和开口矩形是反铁磁性的，可用于数字信息的纳米级记录。
