Germanene : Experimental Study for Graphene Like Two Dimensional Germanium
Germanene : Experimental Study for Graphene Like Two Dimensional Germanium
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锗烯：类石墨烯二维锗的实验研究
DOI：
10.5109/1495160
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
S. Mizuno
中科院分区：
文献类型：
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作者：
S. Rahman;T. Nakagawa;S. Mizuno
受基于石墨烯的丰硕成果的启发，IV族元素（Si、Ge）的二维结构是目前物理学和纳米科学中研究最多的材料。石墨烯的硅类似物硅烯已经实验合成，但石墨烯的锗类似物尚未实验合成。只有少数理论著作预测石墨烯类锗二维蜂窝结构是稳定的、低屈曲的。我们通过低能电子衍射实验观察了 Ag(111) 上锗生长的相演化。我们观察到相演化强烈依赖于 Ag(III) 上的锗覆盖量。我们通过在室温下Ag(III)上的锗吸附获得了(9-/3 x 9-./3)R 30"图案，并且该图案在415 K退火后变得清晰。(9..J3 X 9.ff)R 30°图案类似于SiC(OOOl)上石墨烯形成的(6..J3 X 6.ff)R 30°图案。我们还观察到原子分辨的一张后的STM图像 Ag(ll1) 上的单层锗吸附。通过对STM图像的观察，我们观察到了蜂窝状结构，通过对更大区域的进一步近距离观察，我们观察到了(9-/3 X 9.ff)R 30°莫尔条纹结构。在 LEED 和 STM 结果的基础上，我们提出了锗烯的原子模型，石墨烯的锗类比，在 Ag(III) 上生长。
Inspired by the fruitful results based on graphene, two dimensional structures of group-IV elements (Si, Ge) are currently the most investigated materials in physics and nano science. Silicene, the silicon analogy of graphene, had already been synthesized experimentally, but the germanium analogy of graphene has not been synthesized experimentally yet. Only a few theoretical works predicted that graphene like 2-D honeycomb s1ructure of germanium is stable with low buckling. We experimentally observed the phase evolutions for germanium growth on Ag(111) by low energy electron diffraction. We observed that the phase evolutions were strongly dependent on the amount of germanium coverage on Ag(lll). We obtained a (9-/3 x 9-./3)R 30" pattern by germanium adsorption on Ag(lll) at RT and the pattern become clear after annealing at 415 K.. The (9..J3 X 9.ff)R 30° pattern is analogous to the ( 6..J3 X 6.ff)R 30° pattern of graphene formation on SiC(OOOl). We also observed the atomically resolved STM image after one monolayer germanium adsorption on Ag(ll1). By the observation on the STM image, we observed a honeycomb structure and by further close observation on larger area, we observed the (9-/3 X 9.ff)R 30° moire s1ructure. On the basis of the LEED and STM results, we have proposed an atomic model for germanene, the germanium analogy of graphene, growth on Ag(lll ).