Electronic Structure Modification of Ion Implanted Graphene: The Spectroscopic Signatures of p- and n-Type Doping
Electronic Structure Modification of Ion Implanted Graphene: The Spectroscopic Signatures of p- and n-Type Doping
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DOI：
10.1021/acsnano.5b05305
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发表时间：
2015-11-01
期刊：
影响因子：
17.1
通讯作者：
Ramasse, Quentin M.
中科院分区：
文献类型：
--
作者：
Kepaptsoglou, Demie;Hardcastle, Trevor P.;Ramasse, Quentin M.
结合扫描透射电子显微镜、电子能量损失谱和从头计算，描述了两种单原子掺杂对独立石墨烯电子结构的影响。N K和C K的电子能量损失跃迁表明π *键态的存在，它们高度局域于N掺杂剂周围。相比之下，单个B掺杂原子的bk跃迁表现出不寻常的宽不对称峰，这是远离B掺杂的离域pi*态的结果。bk向高能量方向的不对称性归因于高度定域的sigma*反键态。然后，通过与密度泛函理论计算的仔细比较，这些实验观察结果被解释为以这种方式掺杂的石墨烯的预期p型和n型行为的直接指纹。
A combination of scanning transmission electron microscopy, electron energy loss spectroscopy, and ab initio calculations is used to describe the electronic structure modifications incurred by free-standing graphene through two types of single-atom doping. The N K and C K electron energy loss transitions show the presence of pi* bonding states, which are highly localized around the N dopant. In contrast, the B K transition of a single B dopant atom shows an unusual broad asymmetric peak which is the result of delocalized pi* states away from the B dopant. The asymmetry of the B K toward higher energies is attributed to highly localized sigma* antibonding states. These experimental observations are then interpreted as direct fingerprints of the expected p- and n-type behavior of graphene doped in this fashion, through careful comparison with density functional theory calculations.