中文摘要：

金属表面上的 graphene overlayers 的取向控制是在 Ni 表面上作为挑战留在 graphene 生长的一个重要问题。这里，我们证明了取向附生的 graphene overlayers 能被退火获得五分钱碳化物在 situ 表面成像技术使用的盖住的 Ni (111 ) 表面。取向附生的 graphene 岛在大约 400 点经由溶解的碳原子的分离起核心作用并且成长到最高的表面 ? 吗？？

英文摘要：

The orientation control of graphene overlayers on metal surface is an important issue which remains as a challenge in graphene growth on Ni surface. Here we have demonstrated that epitaxial graphene overlayers can be obtained by annealing a nickel carbide covered Ni（111） surface using in situ surface imaging techniques. Epitaxial graphene islands nucleate and grow via segregation of dissolved carbon atoms to the top surface at about 400 ℃. This is in contrast to a mixture of epitaxial and non-epi- taxial graphene domains grown directly on Ni（111） at 540 ℃. The different growth behaviors are related to the nucleation dynamics which is controlled by local carbon densities in the near surface region.