UNAM-National Nanotechnology Research Center, Bilkent University, 06800 Ankara, Turkey.
J Phys Condens Matter. 2013 Jul 10;25(27):275302. doi: 10.1088/0953-8984/25/27/275302. Epub 2013 Jun 18.
Titanium atoms are adsorbed to graphene with a significant binding energy and render diverse functionalities to it. Carrying out first-principles calculations, we investigated the effects of charging and static electric field on the physical and chemical properties of graphene covered by Ti adatoms. When uniformly Ti covered graphene is charged positively, its antiferromagnetic ground state changes to ferromagnetic metal and attains a permanent magnetic moment. Static electric field applied perpendicularly causes charge transfer between Ti and graphene, and can induce metal-insulator transition. While each Ti adatom adsorbed to graphene atom can hold four hydrogen molecules with a weak binding, these molecules can be released by charging or applying electric field perpendicularly. Hence, it is demonstrated that charging and applied static electric field induce quasi-continuous and side specific modifications in the charge distribution and potential energy of adatoms absorbed to single-layer nanostructures, resulting in fundamentally crucial effects on their physical and chemical properties.
钛原子以显著的结合能吸附在石墨烯上，并赋予其多种功能。通过第一性原理计算，我们研究了充电和静电场对 Ti 原子覆盖的石墨烯物理和化学性质的影响。当均匀覆盖 Ti 的石墨烯被充电为正时，其反铁磁基态变为铁磁金属，并获得永久磁矩。垂直施加的静电场会导致 Ti 和石墨烯之间的电荷转移，并能诱导金属-绝缘体转变。而每个吸附在石墨烯上的 Ti 原子可以弱结合四个氢分子，这些分子可以通过充电或垂直施加电场释放。因此，结果表明，充电和施加的静电场会引起吸附在单层纳米结构上的原子的电荷分布和势能的准连续和侧面特异性修饰，从而对它们的物理和化学性质产生至关重要的影响。
