• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Applied Surface Science >Surface diffusion and coverage effect of Li atom on graphene as studied by several density functional theory methods
【24h】

Surface diffusion and coverage effect of Li atom on graphene as studied by several density functional theory methods

机译：几种密度泛函理论方法研究锂原子在石墨烯上的表面扩散和覆盖效应

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The adsorption of Li atom on graphene is examined using density functional theory methods. Three different adsorption sites are considered, including the on top of a carbon atom (OT), on top of a C-C bond (Bri), and on top of a hexagon (Hol), as well as Li adsorbed at different coverage. The Hol site is found to be the most stable, followed by the Bri and OT sites. The order of stabilization is independent of coverage. The localization of Li-graphene interaction at all sites has reverse order with stabilization. The localization will cause different repulsive interaction between Li atoms which is believed to take responsibility for the difference between the charge transfer order and adsorption energy order of Li adsorption at all possible sites. Repulsive interaction also causes the decreasing of adsorption energies of Li at Hol site with increasing coverage, but the corresponding influence is bigger at low coverage range (0.020-0.056 monolayers) than that at high coverage range (0.056-0.250 monolayers). The trend of charge transfer and dipole moment with increasing coverage is also in agreement with that of adsorption energy. It is also found that the distance of Li above graphene will increase with increasing coverage, but a so-called "zigzag" curve appears, which exhibits an oscillatory behavior as a function of increasing coverage. The diffusion of Li atom on graphene is also studied. Li atom migrates from a Hol site to a neighboring Hol site through the Bri site between them is found to be the minimum energy path. Within the studied coverage range, the diffusion barrier decreases with increasing coverage which can be ascribed to the phenomenon of different repulsion interactions when Li atom adsorbs at different sites. The increasing coverage amplified the phenomenon.
机译：使用密度泛函理论方法研究了Li原子在石墨烯上的吸附。考虑了三个不同的吸附位点，包括碳原子（OT）顶部，C-C键（Bri）顶部和六边形（Hol）顶部，以及在不同覆盖率下吸附的Li。发现Hol站点最稳定，其次是Bri和OT站点。稳定顺序与覆盖范围无关。 Li-石墨烯相互作用在所有位点的定位具有相反的顺序，具有稳定作用。局域化将引起Li原子之间的不同排斥相互作用，这被认为是造成Li吸附在所有可能位置的电荷转移顺序和吸附能级之间差异的原因。排斥性相互作用还导致Hol位点处Li的吸附能随着覆盖率的增加而降低，但是在低覆盖率范围（0.020-0.056单层）下相应的影响大于高覆盖率范围（0.056-0.250单层）。电荷转移和偶极矩随覆盖率增加的趋势也与吸附能的趋势一致。还发现Li在石墨烯上的距离将随着覆盖率的增加而增加，但是出现了所谓的“之字形”曲线，该曲线表现出随覆盖率增加而发生的振荡行为。还研究了Li原子在石墨烯上的扩散。 Li原子通过它们之间的Bri位点从Hol位点迁移到相邻的Hol位点，发现这是最小的能量路径。在研究的覆盖范围内，扩散势垒随着覆盖率的增加而减小，这归因于当Li原子吸附在不同位置时不同的排斥相互作用现象。覆盖率的增加加剧了这一现象。

著录项

  • 来源
    《Applied Surface Science》 |2013年第ptab期|846-852|共7页
  • 作者

    Zhi Ji; Flavio F. Contreras-Torres; Abraham F. Jalbout; Alberto Ramirez-Trevino;

  • 作者单位

    Institute de Ciencias Fisicas, Universidad Nacional Autonoma de Mexico, Av. Universidad 2001, Col. Chamilpa, 62210 Cuemavaca, Morelos, Mexico;

    Institute de Ciencias Nucleares, Universidad National Autonoma de Mexico, Circuito Exterior, Ciudad Universitaria, 04510 Mexico, DF, Mexico;

    Institute Tecnologico de Estudios Superiores de Cajeme, Ciudad Obregon, Sonora, Mexico;

    Institute Tecnologico de Estudios Superiores de Cajeme, Ciudad Obregon, Sonora, Mexico;

  • 收录信息
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

    Graphene; Lithium; Surface diffusion; Density functional theory;

    机译：石墨烯锂;表面扩散;密度泛函理论;

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号